AU2015101974B4

AU2015101974B4 - Staple cartridge including a barbed staple

Info

Publication number: AU2015101974B4
Application number: AU2015101974A
Authority: AU
Inventors: Taylor W. Aronhalt; Emily A. Schellin; Frederick E. Shelton Iv; Michael J. Vendely
Original assignee: Ethicon Endo Surgery LLC
Current assignee: Ethicon Endo Surgery LLC
Priority date: 2014-02-24
Filing date: 2015-02-10
Publication date: 2020-12-24
Anticipated expiration: 2023-02-10
Also published as: CA2940159A1; AU2015101974A4; RU2016137891A; MX2016010957A; RU2682478C2; BR112016019008A8; JP2017506145A; AU2015219430A1; RU2016137891A3; CN106232031A; AU2015219430A2

Abstract

An end effector for fastening tissue, comprising: an anvil, wherein said anvil comprises a deck configured to support tissue, wherein said deck comprises: a first surface, having a first longitudinal row of staple forcing pockets; and a second surface, having a second longitudinal row of staple forming pockets, and wherein said first surface is positioned vertically above said second surface; a cartridge comprising a plurality of staple cavities, wherein said plurality of staple cavities are arranged in first and second longitudinal rows of staple cavities; a plurality of staples removably stored within said staple cavities, and a plurality of staple drivers movable within said staple cavities, wherein said staple drivers are configured to lift said staples toward said anvil, each said staple comprises, a base, a pair of legs extending from said base wherein each said leg has a tip configured to pierce tissue, and wherein each said leg comprises at least two barbs extending from each said leg inwardly toward a center of said staple; and a firing member configured to lift said staple drivers toward said anvil, wherein said firing member comprises a first portion configured to engage said anvil and a second portion configured to engage said cartridge, and wherein said firing member is configured to relatively position said anvil and said cartridge.

Description

TITLE STAPLE CARTRIDGE INCLUDING A BARBED STAPLE BACKGROUND

[0001] The present invention relates to surgical instruments and, in various arrangements, to surgical stapling and cutting instruments and staple cartridges therefor thatare designed to staple and cut tissue.

[0001A] Reference to any prior art in the specification is not an acknowledgment or suggestion that this prior art forms part of the common general knowledge in any jurisdiction or that this prior art could reasonably be expected to be understood, regarded as relevant, and/or combined with other pieces of prior art by a skilled person in the art. SUMMARY

[0001B] In a first aspect, the present invention provides an end effector for fastening tissue, comprising: an anvil, wherein said anvil comprises a deck configured to support tissue, wherein said deck comprises: a first surface, having a first longitudinal row of staple forming pockets; and a second surface, having a second longitudinal row of staple forming pockets, and wherein said first surface is positioned vertically above said second surface; a cartridge comprising a plurality of staple cavities, wherein said plurality of staple cavities are arranged in first and second longitudinal rows of staple cavities; a plurality of staples removably stored within said staple cavities, and a plurality of staple drivers movable within said staple cavities, wherein said m staple drivers are configured to lift said staples toward said anvil, each said staple comprises, a base, a pair of legs extending from said base wherein each said leg has a tip configured to pierce tissue, and wherein each said leg comprises at least two barbs extending from each said leg inwardly toward a center of said staple; and a firing member configured to lift said staple drivers toward said anvil, wherein said firing member comprises a first portion configured to engage ?5 said anvil and a second portion configured to engage said cartridge, and wherein said firing member is configured to relatively position said anvil and said cartridge.

[0001C] In a second aspect, the present invention provides an end effector for fastening tissue, comprising: an anvil comprising a tissue compression portion configured to support tissue, said tissue compression portion comprising: a first compression surface, and a first longitudinal row of staple forming pockets defined in said first compression surface; a second compression surface, and a second longitudinal row of staple forming pockets defined in said first compression surface; a longitudinal slot configured to receive a cutting member, wherein said longitudinal slot divides said tissue compression portion into a first lateral side and a second lateral side, wherein said first compression surface and said second compression surface are positioned on said first lateral side of said longitudinal slot, and wherein said first compression surface is offset from said second compression surface; and a cartridge, comprising: a first deck portion alignable with said first compression surface; a second deck portion alignable with said second compression surface; and a plurality of staple cavities, wherein said plurality of staple cavities are arranged in a first longitudinal row of staple cavities and a second longitudinal row of staple cavities, wherein said first longitudinal row of staple cavities are defined in said first deck portion, wherein said second longitudinal row of staple cavities are defined in said second deck portion, wherein a first gap distance is defined between said first compression surface and said first deck portion, wherein a second gap distance is defined between said second compression surface and said second deck portion, and wherein said first gap distance is different than said second gap distance; a plurality of staples removably stored within said staple cavities, wherein each said staple comprises: a base; and a plurality of legs extending from said base, wherein each said leg comprises a tip configured to pierce tissue, and wherein each said leg comprises at least two barbs extending from said legs inwardly toward a center of said staple; a plurality of staple drivers movable within said staple cavities, wherein said staple drivers are configured to lift said staples toward said anvil; and a firing member configured to lift said staple drivers toward said anvil, wherein said firing member comprises a first portion configured to engage said anvil and a second portion configured to engage said cartridge, and wherein said firing member is configured to relatively position said anvil and said cartridge.

BRIEF DESCRIPTION OF THE DRAWINGS t0002] The features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

[0003] FIG. 1 is a left front perspective view of a surgical stapling and severing instrument with a handle portion; M [0004] FIG. 2 is a perspective view of a two-piece knife and firing bar ("E-beam") of the surgical stapling and severing instrument of FIG. 1;

[0005] FIG. 3 is a perspective view of a wedge sled of a staple cartridge of a staple applying assembly;

[0006] FIG. 4 is a longitudinal cross-sectional view of an anvil in a closed position and a staple !5 cartridge comprising a rigid support portion and a compressible tissue thickness compensator illustrated with staples being moved from an unfired position to a fired position during a first sequence;

[0007] FIG. 5 is another cross-sectional view of the anvil and the staple cartridge of FIG. 4 illustrating the anvil in an open position after the firing sequence has been completed;

[0008] FIG. 6 is an exploded perspective view of a tissue thickness compensator and a staple cartridge assembly;

[0009] FIG. 7 is a partial cross-sectional view of the staple cartridge assembly of FIG. 6, illustrating unfired staples positioned in staple cavities of a staple cartridge body and partially embedded in a tissue thickness compensator;

[0010] FIG. 8 is a partial cross-sectional view of the staple cartridge assembly of FIG. 6, illustrating fired staples ejected from the staple cavities of the staple cartridge body and formed against an anvil, and further illustrating the tissue thickness compensator and tissue captured within the staple entrapment area of the formed staples;

[0011] FIG. 9 is a partial perspective view of an end effector of a surgical fastening instrument illustrated with some portions removed and other portions illustrated in cross-section; moreover, a cutting member of the end effector is illustrated in a partially advanced position;

[0012] FIG. 10 is a partial cross-sectional end view of the end effector of FIG. 9 illustrated with patient tissue captured between an anvil and a tissue thickness compensator of the end 1A effector; moreover, staples removably stored within a cartridge body of the end effector are illustrated in an unfired position and the cutting member of the end effector is illustrated in an unadvanced position which is proximal to the tissue thickness compensator;

[0013] FIG. 11 is a partial cross-sectional end view of the end effector of FIG. 9 illustrated with the staples in a fired position and the cutting member in a partially advanced position in which the patient tissue has been at least partially transected;

1B

[0014] FIG. 12 is partial cross-sectional end-viewof the end effector of FIG. 9 illustratedwiththestaples in afired positionand the cutting member in an advanced position in which at least a portion oF the tissue thickness compensator has ben transected by the cutting member;

[0015] FIG 13 is a perspective view of a fastener cartridge incudiatissue thickness compensator;

[0016] FIG. 14 is a cross-sectional view ofthe tissue thickness compensator of FIG. 13 illustrating a cutting member positioned relative to a proximal endof the tissue thickness compensator.

100171 FIG. 15 is an exploded view of a tissue thickness compensator assembly;

[0018] FIG, 16 is a perspective viewof layer of atissue thickness conpensator assembly;

[0019] FIG. 17 is a cross-sectional view of the tissue thickness compensator assembly ofFIG. 15;

[0020] FIG. 18 is a cross-sectional perspective view of an assembled tissue thickness compensator assembly and a mold for assembling the same;

[0021] FIG, 19 is a perspective viewof the assembled tissue thickness compensatorassembly of FIG. 18;

[0022] FIG. 20 is a perspective view of atissue thickness compensator assembly and a mold for assembling the same; 100231 FIG. 21 is a perspective view of a tissue thickness compensator assembly and a mold for assembling the same;

[0024] FIG. 22 is a cross-sectional perspective view of the tissue thickness compensatorassembly of FIG. 2and the mold of FIG. 21 for assembling the same;

[00251 FIG. 23 is perspective view of an end effector comprising a tissue thickness comnpensator;

[0026] FIG. 24 is a perspective view ofthe end effector and the tissue thickness compensator of FIG. 23 and a modifiyingmember mtodiflin the tissue thickness compensator;

[0027] FIG. 25 is a perspective view ofthe end effector of FIG. 23 comprising the modified tissue thickness compensator of FIG. 24;

[0028] FIG. 26 is a cross-sectional perspective view of a tissue thickness compensator;

[0029] FIG. 27 is a cross-sectional perspective view of a mold formodifying the tissue thickness compensatorof FIG. 26;

[0030] FIG.28isacross-sectionalperspective viewfthetissuethicknesscompensatorofFIG.26after modificatiou by the mold of FIG. 27;

[0031] FIG.29isacrss-sectional perspective viewof a tissue thickness compensator; 100321 FIG. 30 is a cross-sectional perspective view of a mold for modifying the tissue thickness compensator of FIG. 29;

[0033] FIG. 31is a cross-sectional perspective view of the tissue thickness compensator of FIG, 29 after modification by the mold of FIG. 30;

[0034] FIG. 32 is a cross-sectional perspective view ofa tissue thickness com pensator;

[0035] FIG. 33 is a cross-sectional perspective view of a mold for modifying the tissue thickness compensator of FIG. 32;

[0036] FIG. 34 is a cross-sectional perspective view of the tissue thickness compensator of FIG. 32 after modiFicationby the mold of FIG. 33;

[0037] FIG. 35 is a cross-sectional perspective view of a tissue thickness compensator including a first height;

[0038] FIG. 36 is a cross-sectional perspective view ofthe tissue sickness compensator of FIG. 35 after modification to change the first heighttoasecondheight;

[0039] FIG. 37 is a cross-sectional view of a mold for modifying the tissue thickness compensator of FIG. 35;

100401 FIG. 38 is a cross-sectional perspective view of a tissue thickness compensator;

[0041] FIG, 39 is a cross-sectional perspective view thetissue thickness compensator of FIG. 38 aftermodification;

[0042] FIG. 40 is a graph illustrating the effect of compression forces on a springrateof a tissue thickness compensator; 100431 FIG. 41 is a cross-sectional perspective view of a tissue thickness compensator;

[0044] FIG,.42 is across-sectional perspective view of a space creator formodifying thetissue thickness compensator of FIG. 41:

[0045] FIG. 43 is a cross-sectional perspective view of the tissue thickness compensator of FIG. 41 after modification by the space creator of FIG. 42;

[0046] FIG. 44 is apartial cross-sectional elevational view ofafastenercartridge foruse with a surgical instrument including a firing mtremtber inaccordance with at least one embodiment illustrated with portions removed;

[0047] FIG. 45 is a partial cross-sectionalelevationalview depicting a tissue thickness compensator of the fastener cartridge ofFIG. 44 being removed front the fastener cartridge and the firingremiber of FIG. 44 illustrated in a locked-out condition;

[0048] FIG. 46 is apatial perspective view of the tissue thickness compensator of FIG. 45;

[0049] FIG. 47 is a partial perspective view a tissue thickness compensatorinaccordance with at least one embodimrent;

[0050] FIG. 48 is a partial cross-sectional elevational view of an end effector of a surgical instrument comprising a fastenercartridge including the tissue thickness compensator of FIG. 47, a sled, and a firing member supported by the sled illustrated with portions removed;

[0051] FIG,.49 is a partial cross-sectional elevational view of the end effector of FIG. 48 illustrating the firing member in a partially-fired position;

[0052] FIG. 50 is a partial cross-sectional elevational view ofthe end effector of FIG 48 illustrating the tissne thickness compensator removed from the fastener cartridge and the firing member in a locked-out condition:

[0053] FIG. 51 is a partial perspective view of a fastener cartridge in accordance with at least one embodiment illustrated with portions removed

[0054] FIG. 52 is a perspective view of a sled of the fastenercartridge of FIG. 51;

[00551 FIG. 53 is partial perspective view of-the fastenercartridge ofFIG 51;

[0056] FIG. 54 is an elevational view of a sled in accordance with at least one embodiment;

[0057] FIG. 55 is a perspective view of asled in accordance with at least one embodiment iustratedinanunlocked configuration;

[0058] FIG. 56 is perspective view ofthe sled of FIG. 55 illustrated in a locked-out configuration;

[0059] FIG. 57 is a partial cross-sectional elevational view of the sled of FIG 55 positioned within fastener cartridge illustrating the sled in its unlocked configuration, a firing member supported by the sled, and a tissue thickness compensator of the fastener cartridge engaged with the sled;

[0060] FIG. 58 is a partial cross-sectional elevational view ofthe tissue thilckness compensator ofFIG. 57 being removed from the fastener cartridge of FIG. 57 which has placed the sled of FIG,. 55 in itslocked-outconfiguration and the firingmember of FIG. 57 in a locked-out condition;

[0061] FIG, 59 is a partial cross-sectional elevational view ofa sled positioned at the proximal end of a fastener cartridge in accordance with at least one embodimentillustratedwith portions removed;

[0062] FIG. 60 is a partial cross-sectional elevational view of the sled of FIG. 59 illustrated at the distal end of the fastener cartridge;

[0063] FIG, 61 is a perspective viewof a sled in accordance with at least one embodiment;

[0064] FIG. 62 is a diagram depicting a staple comprising a plurality ofbarbs in accordance with at least one embodiment, wherein the staple is illustrated in an unformed configurationand a deformed configuration; 100651 FIG. 63 is an elevational view ofa staple comprising a plurality ofbarbs in accordance with at least one embodiment, wherein the staple is positioned within a staple cavity in anunfired position;

[0066] FIG. 64 is an elevational view of a staple including a plurality of barbs in accordance with at least one enhodiment;

[00671 FIG. 65 is an elevational view of a staple including a plurality ofbarbs in accordance with at least one embodiment;

[0068] FIG. 66 is an elevational view of a staple including a plurality of barbs in accordance with at least one enhodiment;

[0069] FIG, 67 is an elevational view of a staple including a plurality ofbarbs in accordance with at least one embodiment;

[0070] FIG. 68 is an elevational view of the staple including a plhrality of barbs in accordance with at least one embodiment,wherein the staple is positioned within a staplecavityin anunfired position;

[0071] FIG, 69 is a plan view ofthe staple and the staple cavity of FIG. 68;

[0072] FIG. 70 is a partial perspective view ofa barbed stapeleg in accordance with at least one embodiment;

[0073] FIG. 7 1 is a partial perspective view of a barbed staple leg of the staple of FIG. 68; 100741 FIG. 71A is a cross-sectional plan view ofthe barbed staple leg of FIG. 71;

[0075] FIG. 72 is a partial perspectiveview of a barbed staple legion accordance with at least one embodiment; and

[0076] FIG. 73 is a partial perspective view of a barbed staple leg inaccordance with at least one embodiment,

DETAILED DESCRIPTION

[0077] The Applicant of the present application also owns the U.S. Patent Applications identified below which are each herein incorporated byreference in their respective entire:

U.S.Patent Application Serial No. 12/894,311, entitled SURGICAL INSTRUMENTS WITH RECONFIGURABLE SHAFTSEGMENTS; now U.S. Patent Publication No. 2012/0080496; U.S. Patent Application Serial No. 12/894,340, entitled SURGICAL STAPLE CARTRIDGES SUPPORTING NON-LINEARIY ARRANGED STAPLES AND SURGICAL STAPLING INSTRUMENTS WITH COMMON STAPLE-FORMING POCKETS; now U.S. Patent PublicationNo. 2012/0080482; U.S. Patent Application Serial No, 12/894,327, entitled JAW CLOSURE ARRANGEMENTS FOR SURGICAL INSTRUMENTS; now U.S. Patent Publication No. 2012/0080499; U.S. Patent Application Serial No. 12/894,351, entitled SURGICAL CUTTINGAND FASTENING INSTRUMENTS WITH SEPARATE AND DISTINCTFASTENER DEPLOYMENT ANDTISSUE CUTTING SYSTEMS; now U.S. Patent Publication No,.20 12/0080502; U.S. Patent Application Serial No. 12/894,338, entitled IMPLANTABLE FASTENER CARTRIDGE HAVING A NON-UNIFORM ARRANGEMENT; now U.S. Patent Publication No. 2012/0080481; U.S. Patent Application Serial No. 12/894,369, entitled IMPLANTABLE FASTENER CARTRIDGE COMPRISING A SUPPORT RETAINER;now U.S. Patent Publication No. 20 12/0080344; U.S. Patent Application SerialNo. 12/894,312, entitled IMPLANTABLE FASTENER CARTRIDGE COMPRISING MULTIPLE LAYERS, nowU.S. Patent Publication No. 20121/0080479; U.S. Patent Application Serial No. 12/894,377, entitled SLECTIVELY ORINTABLE IMPLANTABLF FASTENER CARTRIDGE; now U.S. Patent No. 8,393,514 U.S. Patent Aplication Serial No. 12/894,339, entitled SURGCAL STAPLING INSTRUMENTWITH COMPACT ARTICULATION CONTROLARRANGEMENT; now U.S. PatentPublicationNo. 2012/0080500; U.S. Patent Application Serial No. 12/894,360, entitled SURGICAL STAPLING INSTRUMENTWITH A VARIABLE STAPLE FORMING SYSTEM; now U.S. Patent Publication No. 2012/0080484; U.S. Patent Atplication Serial No. 12/894,322, entitledSURGICALSTAPLINGINSTRMENTWITH INTERCHANGEABLE STAPLE CARTRIDGE ARRANGEMENTS; now U.S. Patent Publication No. 2012/0080501; U.S. Patent Application Serial No. 12/894,350, entitled SURGICAL STAPLE CARTRIDGES WITH DETACHABLE SUPPORT STRUCTURES; now U.S. Patent Publication No. 2012/0080478; U.S. Patent Application Serial No. 12/894,383, entitled IMPLANTABLE FASTENER CARTRIDGE COMPRISING BIOABSORBABLE LAYERS; now U.S. Patent Publication No. 2012/0080345; U.S. Patent Application Serial No. 12/894,389, entitled COMPRESSIBLE FASTENER CARTRIDGE; now U.S. Patent Publication No.2012/0080335; U.S. Patent Application Serial No 12/894,345, entitled FASTENERS SUPPORTED BY A FASTENER CARTRIDGE SUPPORT; now U.S. Patent Publication No. 2012/0080483; U.S. Patent Application Serial No. 12/894,306, entitled COLLAPSBLE FASTENER CARTRIDGE; now U.S. PatentPublicationNo.2012/0080332;

U.S.Patent Application Serial No. 12/894,318, entitled FASTENER SYSTEM COMPRISING A PLURALITY OF CONNECTED RETENTION MATRIX ELEMENTS; now U.S. Patent Publication No. 20120080480; U.S. Patent Application Serial No. 12/894,330, entitled FASTENER SYSTEM COMPRISING A RETENTION MATRIX AND AN ALIGNMENT MATRIX; now U.S. Patent Publication No. 2012/0080503; U.S. Patent Application Serial No, 12/894,361, entitled FASTENER SYSTEM COMPRISING A RETENTION MATRIX; now U.S. Patent No. 8,529,600; U.S. Patent Application Serial No. 12/894,367, entitled FASTENING INSTRUMENT FOR DEPLOYING A FASTENER SYSTEM COMPRISING A RETENTION MATRIX; now U.S. Patent Publication No. 2012/0080485; U.S. Patent Application Serial No, 12/894,388, entitled FASTENER SYSTEM COMPRISING A RETENTION MATRIXAND A COVER; now U.S. Patent No. 8,474,677; U.S. Patent Application Serial No. 12/894,376, entitled FASTENER SYSTEM COMPRISING A PLURALITY OF FASTENER CARTRIDGES; now U.S. Patent Publication No. 2012/0080486; U.S. Patent Application Serial No, 13/097,865, entitled SURGICAL STAPLER ANVIL COMPRISING A PLURALITY OFFORMING POCKETS; now U.S. Patent Publication No. 2012/0080488; U.S. Patent Apphcation Serial No. 13/097,936, entitled TISSUE THICKNESS COMPENSATOR FOR A SURGICAL.STAPILR;now U.S.Patet Publicat.ionNo%2012/0080339; U.S. Patent Application Serial No. 13/097,954, enitled STAPLE CARTRIDGE COMPRISING A VARIABLE THICKNESS COMPR[SSIBLE PORTION; now U.S. Patent Publication No. 2012/0080340; U.S. Patent Apphcation Serial No. 13/097,856, entitled STAPLE CARTRIDGE COMPRISING STAPLES POSITION )WITHIN A COMPRESSIBLE PORTIONTHEREOFf;now US. Patent Publication No. 2012./0080336; U.S. Patent Aplication Serial No. 13/097,928, entitled TISSUE THICKNESS COMPENSATOR COMPRISING DETACHABLE PORTIONS; now U.S. Patent Publication No. 2012/0080490; U.S. PatentAlieation SerialNo13/097,891, entitledTISSUETHICKNESS COMPENSATOR FOR A SURGICAL STAPLERCOMPRISING AN ADJUSTABLE ANVIL; nowU.S. Patent PublicationNo. 2012/0080489; U.S. Patent Application Serial No. 13/097,948, entitled STAPLE CARTRIDGE COMPRISING AN ADJUSTABLE DISTAL PORTION; now U.S. Patent Pubtication No. 2012/0083836; U.S. Patent Application Serial No, 13'097,907, entitled COMPRESSIBLE STAPLE CARTRIDGE ASSEMBLY; now U.S. Patent Publication No. 2012/0080338; U.S. PatentApplication Serial No. 13/097,861, entitled TISSUE THICKNESS COMPENSATOR COMPRISING PORTIONS HAVING DIFFERENT PROPERTIES; nowU.S. Patent Publication No. 2012/0080337; U.S. Patent Application Serial No. 13/097,869, edited STAPLE CARTRIDGE LOADING ASSEMBLY; now US. Patent Publication No. 2012/0160721: U.S. Patcit Application Serial No. 13/097,917, entitled COMPRESSIBLE STAPLE CARTRIDGE COMPRISING ALIGNMENTMEMBERS; now U.S. Patent PublicationNo. 2012/0083834;

U.S.Patent Application Serial No. 13/097,873, entitled STAPLE CARTRIDGE COMPRISING A RELEASABLE PORTION; now U.S Patent Publication No, 2012/0083833; U.S. Patent Application Serial No. 13/097,938, entitled STAPLE CARTRIDGE COMPRISING COMPRESSIBLE DISTORTION RESISTANTCOMPONENTS now U.S. Patent Publication No. 20 12/0080491; U.S. Patent Application Serial No. 13/097,924, entitled STAPLE CARTRIDGE COMPRISING A TISSUE THICKNESS COMPENSATOR; now U.S. Patent PublicationNo. 2012/0083835; U.S. Patent Application Serial No. 13/242,029, entitled SURGICAL STAPLER WITH FLOATING ANVIL; now U.S. Patent Pibliation No,20 12/0080493; U.S. Patent Application Serial No. 13/242,066, entitled CURVED END EFFECTOR FOR A STAPLING INSTRUMENT; now U.S. Patent Publication No, 2012/0080498; U.S. Patent Application Serial No. 13/242,086, entitled STAPLE CARTRIDGE INCLUDING COLLAPSIBLE DECK; now U.S. Patent Publication No. 2013/0075450; U.S. Patent Application Serial No. 13/241,912, entitled STAPLE CARTRIDGE INCLUDING COLLAPSIBLE DECK ARRANGEMENT; now U.S. Patent Publication No, 2013/0075448; U.S. Patent Application Serial No. 13/241,922, entited SURGICAL STAPLER WITH STATIONARY STAPLE DRIVERS; now U.S. Patent Publication No. 2013/0075449; U.S. Patent Application Serial No. 13/241,637, entitled SURGICAL INSTRUMENTWITHTRIGGER ASSEMBLY FOR GENERATING MULTIPLE ACTUATION MOTIONS;now U.S. Patent Publication No. 2012/0074201; U.S.Patent Application Serial No. 13/241,629, entitled SURGICAL INSTRUMENT WITH SELECTIVELY ARTICULATABLE END EFFECTOR; now U.S. Patent Pubication No. 2012/0074200; U.S. Application Serial No. 13/433,096, entitled TISSUE THICKNESS COMPENSATOR COMPRISING A PLURALITYOFCAPSULES;now U.S. Patent Publicatio No. 2012/0241496; U.S. Application Serial No. 13/433,103, entitledTISSUE-THICKNESS COMPENSATOR COMPRISING A PLURALITY OF LAYERS; now U.S. Patent Publication No, 2012/0241498; U.S. Application Serial No. 13/433,098, entitled EXPANDABLETISSUE THICKNESS COMPENSATOR; now U.S. Patent Publication No,2012/0241491; U.S. Application Serial No. 13/433,102, entitledTISSUETHICKNESS COMPENSATOR COMPRISING A RESERVOIR; now 1.S. Patent Publication No. 2012/0241497; U.S. Application Serial No. 13/433,114, entitled RETAINER ASSEMBLY INCLUDING ATISSUE THICKNESS COMPENSATOR; now U.S. Patent Publication No. 2012/0241499; U.S. Application Serial No. 13/433,136, entitled TISSUETHICKNESS COMPENSATOR COMPRISING AT LEAST ONE MEDICAMENT; now U.S. Patent Piblication No. 2012/0241492; U.S. Application Serial No. 13/433,141, entitledTISSUETH1ICKNESS COMPENSATOR COMPR[SING CONTROLLED RELEASE AND EXPANSION; now U.S. Patent Piblication No. 2012/0241493; U.S. Application Serial No. 13/433,144, entitled TISSUE THICKNESS COMPENSATOR COMPRISING FIBERS TO PRODUCE A RESILIENT LOAD; now U.S. Patent Publication No. 2012/0241500;

U.S.Application Serial No. 13/433,148.,entitled TISSUE THICKNESS COMPENSATOR COMPRISING STRUCTURETO PRODUCE A RESILIENTLOAD; now U.S. Patent Publiation No.2012/0241501; U.S. Application Serial No. 13/433,155, entitled TISSUE THICKNESS COMPENSATOR COMPRISING RESILIENTMEMBERS; now U.S. Patent Publication No. 2012/0241502; U.S.ApplicationSerialNo. 13/433,163.,entitled METHODS FOR FORMING TISSUE THICKNESS COMPENSATOR ARRANGEMENTS FOR SURGICAL STAPLERS now U.S. Patent Publication No. 2012/0248169; U.S. Atplication Serial No.13/433,167, entitled TISSUE THICKNESS COMPENSATORS; now U.S. Patent Publication No. 2012/0241503; U.S. Application Serial No. 13/433,175, entitled LAYERED TISSUETHICKNESSCOMPENSATORnow US. Patent Publication No. 2012/0253298; U.S. Application Serial No. !!3/433,179, entitled TISSUE THICKNESS COMPENSATORS FOR CIRCULAR SURGICAL STAPLERS; now U.S. Patent Publication No.2012/0241505; U.S. Application SerialNo. 13/763,028, entitled ADHESIVE FILM LAMINATE; now US. Patent Publication No. 2013/0146643; U.S. Application Serial No. 13/433,115,entitled TISSUE THICKNESS COMPENSATOR COMPRISING CAPSUiESDEFININGALOWPRESSUREENVIRONMEN] iowU.S.Patnit llPublication No.2013 1 256372' U.S. ApplicationSeriaNo. 13/433,118,entitled TISSUE THICKNESS COMPENSATOR COMPRISED OF APLURAL[ITY'OFMATERIALS; nowU.S. Patent Publication No. 013/0256365; U.S. Application Serial No. 13/433,135,entitled MOVABLE MEMBER FOR USE WITH A TISSUE THICKNENSS COMPENSATOR; now US Patent PuNictionNo 2013/0256382; U.S. Application Serial No. 13/433,140, entitled TISSUE THICKNESS COMPENSATOR AND METHOD FOR MAKING THE SAME;now U.S. Patent PuliEcation No,2013/0256368; U.S. Application Serial No. 13/433,129, entitledTISSUE-THICKNESS COMPENSATOR COMPRISING A PLURALITY OF MEDICAMENTS; now U.S. Patent Publication No. 2013/0256367; U.S. Aplication Serial No. 11/216, entited STAPLE CARTRIDGES FOR FORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. Patent No, 7,669,746; U.S. Application Serial No. 11/714,049, entitled SURGICAL STAPLING DEVICE WITH ANVIL HAVING STAPLE FORMING POCKETS OF VARYING DEPTHS, now U.S, Patent Publication No, 2007/0194082; U.S. Application Serial No. 11/711,979,entitled SURGICAL STAPLING DEVICES THAT PRODUCE FORMED STAPLES HAVING IFFERENTLENGTHS,now US Patent No. 8,317,070; U.S. Application Serial No. 11/711,975, entitled SURGICAL STAPLING DEVICE WITH STAPLE DRIVERS OF DIFFERENTHEIGHT, now U.S. Patent Publication No. 2007/0194079; U.S. Application Serial No. 11/711,977, entitled SURGICAL STAPLING DEVICE WITH STAPLE DRIVER THAT SUPPORTS MULTIPLE WIRE DIAMETER STAPLES, now U.S. Patent No.7,673,781;

U.S.Application Serial No. 11/712,315,entitled SURGICAL STAPLING DEVICE WITH MULTIPLE STACKED ACTUATOR WEDGE CAMS FOR DRIVING STAPLE DRIVERS, now US, Patent No. 7,500,979; U.S. Application Serial No. 12/038,939, entitled STAPLE CARTRIDGES FOR FORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. Patent No. 7,934,630; U.S. Application Serial No. 13/020,263.,entitled SURGICAL STAPLING SYSTEMS THAT PRODUCE FORMED STAPLES HAVING DIFFERENT LENGTHS, now U.S. Patent Publication No.2011/0147434; U.S. Application Serial No. 13/118,278, entitled ROBOTICALLY-CONTROLLED SURGICAL STA PLING DEVICES THAT PRODUCE FORMED STAPLES HAVING DIFFERENT LENGTHS, now U.S. Patent Publication No. 2011/0290851; U.S. Application SerialNo. 13/369,629, entitled ROBOTICALLY-CONTROLLED CABLE-BASED SURGICAL END EFFECTORS, now U.S. Patent Publication No. 2012/018660; U.S. Application Serial No. 12/695,359, eitiled SURGICAL STAPLING DEVICES FOR FORMING STAPLES WITH DIFFERENTFORMED HEIGHTS, now U.S. Patent No. 8,464,923; U.S. Application Serial No. 13/072,923, entitled STAPLE CARTRIDGES FOR FORMING STAPLES HAVING DIFFERING FORMED STAPLE HEIGHTS, now U.S. Patent No.8,567,656; U.S. Application Serial No. 13/766,325, entitled LAYER OF MATERIAL FOR A SURGICAL END EFFECTOR;now U.S. Patent Publication No.2013/0256380; U.S. Application Serial No. 13/763,078, entitled ANVIL LAYER ATTACHED TO A PROXIMAL END OF AN END EFFECTORt now U.S. Patent Publication No. 2013/0256383; U.S. Application Serial No. 13/763,094,entitled LAYER COMPRISING DEPLOYABLE ATTACHMENT MEMBE1RS; now1U9S.Paent PbicationNo2013/0256377; U.S. Application Serial No. 13/763,106, entitledEND EFFECTOR COMPRISING A DISTAL TISSUE ABUTMENT MEMBER; now U.S, Patent Publication No,2013/0256378; U.S. Application Serial No. 13/433,147. entitled TISSUETHICKNESS COMPENSATOR COMPRISING CHANNELS; now S Pate -Publication No.2013/0256369; U.S. Application Serial No. 13/763,112, entitled SURGICAL STAPLING CARTRIDGE WITH LAYER RETENTION FEATURES; now U.S. Patent Publication No,2013/0256379; U.S. Application Serial No. 13/763,035, entitled ACTUATOR FOR RELEASING A TISSUETHICKNESS COMPENSATOR FROM A FASTENER CARTRIDGE; now U.S. Patent Publication No. 2013/0214030; U.S. Application Serial No. 1 3/763,042, entitled RELEASABLETISSUE THICKNESS COMPENSATOR AND FASTENER CARTRIDGE HAVING THE SAME; now U.S. Patent Publication No. 2013/0221063; U.S. Application SerialNo. 13/763,048, entitled FASTENER CARTRIDGE COMPRISING A RELEASABLE TISSUE THICKNESS COMPENSATOR; now U.S. Patent Publication No.2013/0221064; U.S. Application Serial No. 13/763,054, entitled FASTENER CARTRIDGE COMPRISING A CUTTING MEMBER FOR RELEASING A TISSUE THICKNESS COMPENSATOR;

U.S. Application Serial No. 13/763,065, entitled FASTENER CARTRIDGE COMPRISING A RELEASABLYA'TTACHlED TISSUE THICKNESS COMPENSATOR; now U.S. Patent Publication No. 2013/0221065; U.S. Application Serial No. 13/763,021, entitled STAPLE CARTRIDGE COMPRISING A RELEASABLE COVER: U.S. Application SeriaNo. 13/763,078, enitled ANVIL LAYER ATTACHED TO A PROXIMAL END OF AN END EFFECTOR; now U.S. Patent Publication No. 2013/0256383; U.S. Atplication Serial No. ]3/763,095, entitled LAYER ARRANGEMENTS FOR SIJRGICAL STAPLE CARTRIDGES; now U.S. Patent Publication Nzo 203/0161374; U.S. Application Serial No. 13463,i47, entitled IMPLANTABLE ARRANGEMENTS FOR SURGICAL STAPLE CARTRIDGES now U.S. Patent Publication No. 2013/0292398; U.S. Atplication Serial No. i3/763,192, entitled MULTIPLE THICKNESS IMPLANTABLE LAYERS FOR SURGICAL STAPLING DEVICES; now U.S. Patent Publication No. 2013/0146642; U.S. Application SerialNo. 13/763,161, entitld RELEASABLE LAYER OF MATERIAL AND SURGICAL END EFFECTOR HAVING THE SAME; now U.S. Patent Publication No. 2013/0153641; U.S. Application Serial No. 13/763,177, entitled ACTUATOR FOR RELEASING A LAYER OF MATERIAL FROM A SURGICAL END EFFECTOR; now U.S. Patent Publication No 2013/0146641; U.S. Application Serial No. 3/763,037, entitled STAPLE CARTRIDGE COMPRISING A COMPRESSIBLE PORTiON U.S. Application Serial No. 13/433,126. entitled TISSUE THICKNESS COMPENSATOR COMPRISING TISSUI INGROWTH FEATURES; now U.S. Patent Publication No. 2013/0256366 U.S. Application Serial No. 13/433,132, entitled DEVICES AND METHODS FOR ATTACHING TISSUE THICKNESS COMPENSATING MATERIALS TO SURGICAL STAPLING INSTRUMENTS; nowU.S. Patent Publication No.2013/0256373. U.S. Application SerialNo. 13/851,703, entitled FASTENER CARTRIDGE COMPRISING A TISSUE THICKNESS COMPENSATOR INCLUDING OPENINGS THEREIN; U.S. Atplication Serial No. 1 3/851,676,entitled TISSUE THICKNESS COMPENSATOR COMPRISING A CUTTING MEMBER PATH; U.S. Application Serial No. 13/851,693, entitled FASTENER CARTRIDGE ASSEMBLIES; and U.S. Application Serial No. 13/851,684, entitled FASTENER CARTRIDGE COMPRISING TISSUE THICKNESS COMPENSATOR AND A GAP SETTING ELEMENT.

[0078] Applicant ofithe present application alsoownsthefollowing patentalicatonsthat were filedon even date herewith and which are each herein incorporated by reference in theirrespective entireties: U.S. Patent Application Serial No. , entitled STAPLE CARTRIDGE INCLUDING A BARBI) STAPLE, AttorneyfDocket No. END7439USNP; U.S. Patent Application SerialNo. , entied STAPLE CARTRIDGE INCLUDING A BARBED STAPLE, Attorney Docket No. END7441USNP;

SPatent Application Serial No._,------- entitled IMPLANTABLE LAYERS COMPRISING A PRESSED REGION, Attorney Docket No. END7349USNP/130323; U.S. Patent Application Serial No. , entitled IMPLANTABLE LAYERS AND METHODS FOR ALTERING ONE OR MORE PROPERTIES OF IMPLANTABLE LAYERS FOR USE WITH FASTENING INSTRUMENTS, Attorney Docket No. END7348USNP/130324; U.S. Patent Aplication Serial No._, entitled IMPLANTABLE LAYERS AND METHODS FOR MODIFYING THE SHAPE OFTTHE IMPLANTABLE LAYERS FOR USE WITH A SURGICAL FASTENING INSTRUMENT, Attorney Docket No, END7347USNP/130325; U.S. Patent Application SerialNo. , entitled IMPLANTABLE LAYER ASSEMBLIES, Attorney Docket No. END7346USNP/130326; U.S. Patent Application Serial No. , entitled IMPLANTABLE LAYERS COMPRISING A PRESSED REGION, Attorney Docket No. END7345USNP/130327; and U.S. Patent Application SerialNo. , entitled FASTENING SYSTEM COMPRISING A FIRING MEMBER LOCKOUT, Attorney Docket No. END7350USNP/130328. 100791 Certain exemplary embodiments will now be described to provide an overall understanding ofthe principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are ilustrated in the accompanying drawings. Those of ordinary skillin the art williunderstand that the devices and methods specifically described herein and illustrated inthe accompanying drawings are non himting exemplary embodimentsand that the scope of the various embodiments of the present invention is deined solely by the claims. The features illustrated ordescribedin connection with one exemplary embodiment may be combinedwithrthe featuresofother embodiments.Suchmodificationsandvariationsareintendedtobeincluded within the scope of the present invention.

[0080] Theterms'comprise"(andanyformofcomprse,suchas"comprises"and"comprising"),"have"(andany form of have, such as "has" and "having"), "include" (and any form of-include, such as "includes" and "including") and "contain" (and any form ofcontain, such as "contains" and "containing") are open-ended linking verbs. As a result, a surgical system, device, or apparatus that "comprises," "has," "includes"or "contains" one or more elements

possesses those oneor more elements, but is not limited to possessing only those one ormore elements. Likewise, an element of a system, device, or apparatus that "comprises," "has," "includes" or "contains"one or more features possesses those one ormore features, but is not limitedtopossessiug only those one ormore eatures. 100811 The terms'"proximal" and "distal" are usedherein with reference to a clinicianmanipulating the handle portion of the surgical instrument. The tern proximall" referring to the portionclosest to the clinician and the term "distal" referring to the portion located away from the clinician It will be trther appreciated that, forconvenience and clarity, spatial terms such as "vertical", "horizontal", "up",and "down" may be used herein with respect to the drawings. However, surgical instruments are used inmany orientations and positions, and these terms are not intended to be limiting and/or absolute.

[0082] Various exerplary devicesand methods are provided for performing laparoscopic and minimally invasive surgicalprocedures. However, the person of ordinary skillin the art will readily appreciate that the various methods and devices disclosed herein can be used innumerous surgical procedures and applications including, for example, in connection with open surgical procedures. As the present Detailed Description proceeds, tlose of ordinary skill in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, throuhanincision orpuncture hole formed in tissue, etc, Theworking portions orenld effector portions ofthe instruments can be inserted directly into a patient's body or can be inserted through an access device that has a working chartel through which the end effector and elongated shaft aicarstrlument can be advanced.

[0083] Turning to the Drawings wherein like numerals denote like components throughout the several views, FIG. I illustrates an exemplary surgical stapling and severing instrument 8010 suitable for use with a tissuethickness compensator assembly as described in greater detail below. The surgical stapling and severing instrument 8010 can comprise an anvil 8014 which may be repeatedly opened and closed about its pivotal attachment to an elongate staple channel 8016. A staple applying assembly 8012 may comprise the anvil 8014 and the channel 8016, wherein the assembly 8012 can be proximally attached to an elongate shall 8018 forcing an implement portion 8022. When the staple applying assembly 8012 is closed, or at least substantially closed, the implement portion 8022 can present a sufficiently smal cross-section suitable for insertingthe staple applying assembly 8012 through a trocar. In various circumstances, the assembI 8012 can be manipulated by a handle 8020 connected to the shaft 8018. Thehandle8020 can compriseuser controls such as a rotation knob 8030 that rotates the elongate shaft 8018 and the staple applying assembly 8012 about a longitudinal axis of the shaft 8018. A closure trigger 8026, which cantpivot in front of a pistol

grip8036 to close the staple applying assembly 80'2, A closure release button 8038 can be outwardly presented on the handle 8020 when the closure trigger 8026 is clamped such that the release button 8038 can be depressed to unclamp the closure trigCer 8026 and open the staple applying assembly 8012, or example. A firigtrigger 8034, which can pivot in front of the closure trigger 8026, can cause the staple applying assembly 8012 to simultaneousv sever and staple tissue clamped therein. In various circumstances, multiple firing strokes cant be emloyed usintgthe firing trigger 8034 to reduce the amount of force required to be applied by the surgeon's hand per stroke. Incertain embodiments, thehandle8020cancotnpriseorneortmore rotatableiidicator wheels such as, for example, rotatable indicator wheel 8041which can indicate the firing progress. A manual firingrelease lever 8042 caniallow the firing system to be retracted before full firing travel has been completed, ifdesired, and, in addition, the firing release lever 8042 can allow a surgeon, or other clinician, to retract the iring system in the eventthat the firing system binds and/or fails. Additional details on the surgical stapling and severing instrument 8010 and other surgical stapling and severing instruments suitable for use with the present disclosure are described, for example, in U.S. PatentApplication No. 13/851,693, entitled FASTENER CARTRIDGE ASSEMBLY, and filed on March 27, 2013, the entire disclosure of which is incorporated herein by reference. Furthermore, powered surgical staplitg and severing instruments can also be utilized with the present disclosure. See, for example, U.S. Patent Application Publication No. 2009/0090763A, entitled POWERED SURGICAL STAPLING DEVICE, and filed on August 8, 2008, the entire disclosure ofwhich is incorporated herein byreference.

[0084] With reference to FIGS. 2 and 3, a firing assembly such as, for example, firingassembly 9090 can be utilized with the surgical stapling and severing instrument 8010 to advance a wedge sled 9126 which comprises a plurality of wedges 9204configured to deploy staples from the staple applying assembly 8012 into tissue captured between the anvil 8014 and the elongate staple channel 8016. Furthermore, an E-bean 9102 a: a distal portion of the firing assembly 9090 may facilitate separateclosure and firing as well as spacing of the anvil 8014 from the elongate staple channel 8016 during firing. Tle E-beam 9102 may include a pair of top pis 9110, a pair o" middle pins 9112which may follow portion 9218 of the wedge sled 9126, and a bottom pinor foot 9114, as well as a sharp cutting edge 9116 which can be configured to sever the captured tissue as the firing assembly 9090 is advanced distally. In addition, integrally forced and proximally projecting top guide 9118 and middle guide 9120 bracketing each vertical end ofthe cutting edge 9116 may further define a tissue staging area 9122 assisting in guiding tissue to the sharp cutting edge 9116 prior to being severed. The middle guide 9120 may also serve to engageand firethe staple applying assembly 8012 by abutting a stepped central member 9124 of the edge sled 9126 (FIG. 2) that effects staple formation by the staple applying assembly 8012.

[0085] In various circumstances, a staple cartridge can comprise means for compensating for thickness of tissue captured within staples deployed from a staple cartridge. Referring to FIG. 4, a staple cartridge, suchas staple cartridge 10000, for example, can be utilized vith the surgical stapling and severing instrument 8010 and can include rigid first portion, such as support portion 10010, for example, and a compressible second portion, such as tissue thickness compensator 10020, for example. The support portion 10010 can comprise a cartridgeobody and aplurality of staple cavities 10012, A staple 10030, for example, can be removably positioned in each staple cavity 10012. Referring primarilyto FIGS. 4 and 5, each staple 10030 can comprise a base 10031 and one or more legs 10032 extending from the base 10031. Prior to te staples 10030 being deployed, the bases 10031 of the staples 10030 can be supported by staple drivers positioned within the support portion 10010 and, concurrently, the legs 10032 of the staples 10030 can be a: least partially contained within the staple cavities 10012 Invarious circumstances, the staples 10030 can be deployed between an unfired position and a fired position such that the legs 10032 move through the tissue thickness compensatory 10020, penetrate through a top surfaceof the tissue thickness compensatory 10020, penetrate the tissueT, and contact an anvil positioned opposite the staple cartridge 10000. As the legs 10032 are deformed against the anvil, the legs 10032 of each staple 10030 can capture a portion of the tissue thickness comensator 10020 and a portion ofthe tissue Twithin each staple 10030 and apply compressive force to the tissue. Further to the above, the legs 10032 ofeach staple 10030 can be deformed downwardly toward the base 1003 ofthe stapleto form a staple entrapment area in which the tissueT and the tissuethickness corupensator 10020 can be captured. In various irctmistances, the staple entrapent area canbe defined between the inner surfaces ofthe defied les 10032 and theinner surface of the base 10031. The size of the entrapment area for a staple can depend on several factors such as the length of the legs, the diameter of the legs, the width ofthe base, and/or the extent in which the lees are deformed, for example.

[0086] In use, furtherto the above and referringprimarily to FIG. 4, an anvil, such as anvil 8014 of the surgical stapling and. severing instrument 8010, cart be moved into a closed position opposite the staplecartridge 10000 by depressing the closure trigger 8026 to advance the E-beam 9102. The anvil 8014 can position tissue against the tissue thickness compensator 10020 and, in various circumstances, compress the tissue thickness compensatory 10020against the support portion 10010, for example. Once the anvil 8014 has been suitably positioned, the staples 10030 can be deployed, as also illustrated in FIG. 4. In various circumstances, asmentioned above, a staple-firing sled 10050, which is similar in many respects to the sled 9126 (See FIG. 3), can be roved froma proximal end of the staple cartridge 10000 toward a distal end 10002, as lustrated in FIG. 5. As the firing assembly 9090 is advanced, the sled 10050 can contact the staple drivers 10040 andlift the staple drivers 10040 upwardly within the staple cavities 10012. In at least one example, the sled 10050 and the staple drivers 10040 can each comprise one ormore ramps, or inclined surfaces, which can co-operate to move the staple drivers 10040 upwardly from their unired positions. As the staple drivers 10040 are lifledupwardly within their respective staple cavities 10012, the staple drivers 10040 can lift the staples 10030 upwardly such that the staples 10030 can emerge from their staple cavities 10012. In various circumstances, tie sled 10050 can move several staples upwardly at the same time as part of a firing sequence.

[0087] As discussed above, and referring to FIG. 5, the staple legs 10032 of the staples 10030 can extend into the compensator 10020 eyond the support portion 10010 when the staples 10030 are in theirunfired positions. In various circumstances, the tips of the staple legs 10032, or any other portion of the staple legs 10032, may not protrude through a top issue-contacting surface 10021 of thetissue thickness compensator 10020 when the staples 10030 are in theirunfired positions. Uncertain circumstances, the tips of the staple legs 10032 can comprise sharp tips which can incise and penetrate the tissue thicklesscompensator 10020.

[0088] In various circumstances, it may be preferable to prevent and/or limit frictional forces between a tissue thickness compensator and a staple. Referring now to FIGS. 6-8, a tissue thickness compensator 20220 for use with a staple cartridge assembly 20200can include a phirality offclearance apertures 202 24 extending at leastnartiallv through the tissue thickness compensator 20220. N various circumstances, the staple cartridge assembly 20200 can include a staple cartridge body 20210 and a tissue thickness compensator 2020 releasably secured relative tothe staple cartridge body 20210. 'The cartridge body 20210 can include a cartridge deck 20211 and a phtraity of staple cavities 20212 defined throughtheeartridgedeck 202 11 and into the body of the staple cartridge body 20210, for example. Staples 20230 can be removably positioned in the staple cavities 20212, for example. The tissue thickness compensator 20220 can include a tissue-contacting surface 20221 (FIG. 7) and a deck-contacting surface 20222 (FIG. 6), The deck-contacting surface 20222 can be releasably positioned against the deck 20211 ofthe cartridge body 20210, for example, andthe tissue-contacting surface 20221 can be positionedagainsttissueTtobesaped,for example. Clearance apertures 20224 can extend through the deck-contacting surface 20222 and intotetissue thickness compensator 20220 and may comprise holes, slits, gaps, bores, openings, and/or cleared pathways, for example, within the tissue thickness compensator 20220 100891 Referring primarily to FIGS. 7 and 8, staples 20230 can be positioned in the staple cavities 20212 ofthe cartridge body 20210. Each staple 20230 can include a base 20231 and a pair of staple legs 20232, for example, which can extend from the base 20231. Each staple leg 20232 can extend from opposite ends of the base 2023 Referring primarily to FIG. 7, one or more of the clearance apertures 20224 in the tissue thickness compensator 20220 canincludeaniopeninginthedeck-cotactingsurface0222.Theopening ofaclearanceaperture20224wcan be aligned with a corresponding staple leg 20232 that is positioned in a staple cavity 20212. For example, a single staple leg 20232 can be lined with the opening of a single clearance aperture 20224whe ithe tissue thickness compensator 20220 is secured relative to the cartridge body20210. In certain circumstances, a staple leg 20232 can extend into each clearance aperture 20224, such thatat least a portion ofthe staple 20230 is embeddedin the tissue thickness compensator 20220, forexample. For example, referring uimarly to FIG. 7, a staple 20230 can include a first staple leg20232a and a second staple leg 20232b. Furthermore, the tissue thickness compensator 20220 can include a first clearance aNerture 20224a aligned with the first staple leg 20232a, and a secondclearance aperture 20224b aligned with the second staple leg 20232b, for example. Priortodeployment ofthe staple 20230,the first stapleleg 20232a can extend partially through the first clearance aperture 20224a, and the second staple leg 20232b can extend partially through the second clearance aperture 20224b, for example. The tissue thickness compensator 20220 can include additional clearance apertures 20224 that are not aligned with staple legs 20232, for example. In certain circumstances, the staple cartridge assembly 20200 can include additional staples 20230 and/or staple legs 20232 that arenotaligned with clearance apertures 20224, forexample. 100901 The staples 20230 can be moveable from an unfired configuration (FIG. 7) to a fired configuration (FIG. 8). Each staple 20230 ca be moved along a staple axis when moving between the fired configuration and the fired configuration. When in the unfired configuration, the staple legs 20232 can extend from the staple cavities 20212 and itto the tissue thickness compensator 20220, for example. The staple legs 20232 can be partially embedded in the tissue thickness comnensator 20220 when the staples 20230 are in the unfired configuration, for example. Furthermore, at least a portion of the staple legs 20232 can be aligned with and/or positioned within the clearance apertutres 20224 of the tissue thickness compensator 20220 when the staples are inthe unfired configuration, for example. In other circumstances, the staple legs 20232 can be positioned entirely within the staple cavity 20212 when intheunfired configuration, and can be aligned with the clearance apertures 20224 positioned above the cartidge deck 20211 (FIG. 6), for example.

[0091] The staples 20230 can move from the unfired configuration (FIG. 7) tothe firet -onfiguration(FIG. 8) during a firing stroke, as described herein. A staple driver 20240 can be positioned within each staple cavity 20212. The staple driver 20240 within each staple cavity 20212 can be pushed toward the cartridge deck 20211 (FIG 6), for example, to drive the staple 20230intotissueT anid toward an anvil 20260 (FIG. 8) which can be similarin many respects toother anvils described herein such as, for example, the anvil 8014 (FIG. 1). As each staple 20230moves from the unfired configuration to the fired configuration, the staple legs 20232 can move through the clearance apertures 20224 in the tissue thickness competitor 20220. The clearance apertures 20224 can have a predemed trajectory within the tissue thickness compensator 20220. For example, the clearance apertures 20224 can extend along an axis that is perpendicular to and/or substantially perpendicular to the tissue-contacting surface 20221 (FIG. 7) and/or the deck-contacting surface 20222 (FIG. 6) o'thetissuethickness compensator 20220. In other circumstances, the clearance apertures 20224 can extend along an axis hat is oriented at an oblique angle relative to the tissue contactingsurface20221 aud/or the deck-contacting surface 20222 of the tissue thickness compensator 20220, for example. In certain circumstances, a group ofthe clearance apertures 20224 catbe parallel. In some circumstances, all offthe clearance apertures 20224 within the tissue thickness compensatort20220 can be parallel, for example. The clearance apertures 20224 can comprise a partially curved trajectory o andor a partially linear trajectory. Other characteristics and Ifeatures ofthe clearance apertures 20224 are described ii greater detail in U.S. Patent Application No.13/851,693, entitled FASTENER CARTRIDGE ASSEMBLY, and filed on March 27, 2013, the entire disclosure of which is incorporated herein by reference. Methods and techniques for modifting a tissue thickness compensator to include clearance apertures such as, for example, the clearance apertures 20224 are described below in greater detail.

[0092] Referring now to FIGS. 9-12, an end effector 22090 of a surgical instrument similar in many respects to the surgical instrument 8010, forexample, can comprise afirst jaw including a fastener cartridge assembly 22000 and a secondjaw including an anvil 10060. The firstjaw can include a staple cartridge channel 10070 which can be configured to removablv receive the cartridge assembly 22000. Alteratively, the staple cartridge channel 10070 and the cartridge assembly 22000 can comprise an integral unit. In various circumstances, the anvil 10060 can be moved between an open position and a closed position (FIGS. 9-12). In the open position of the anvil 10060, the anvil 10060 can be positioned on a first side of a patient'stissueT (FIGS. 10-12) and the cartridge assembly 22000 can be positioned on a second, or opposite, side of the tissue T, for example. When the anvil 10060 ismoved into its closed position, the anvil 10060 can compress thetissue Tcagainst the cartridze assembly 22000. Alternatively, the firstjaw including the cartridge assembly22000 can be moved relative to the anvil 10060. A firing member 10052, which is similar many respects to the ring assembly 9090 (FIG 3), can be advanced distally from proximal end 22001 of the cartridge assembly 22000 toward a distal end 22002 ofthe cartridge assembly 22000 to eject fasteners, such as staples 22030, for example, removably stored in a cartridge body 22010 ofthe cartridge assembly 22000 as the firing member 10052 is advanced from the proximal end 22001 toward the distal end 2002 of the cartridge assembly 22000.

[0093] Further to the above, the staples 22030 can be supported by staple drivers 10040 which are movably positioned within staple caviities 22012 defined in the cartridgebody'22010 Moreover, thefiring member10052 can beconfigured to advance a staple-fing sled 10050 distally within the cartridge body 22010 as the firing member 10052 is moved from the proximal end 22001 toward the distal end 22002. in such circumstances, the staple-firing sled 10050 can be configured to lift the staple drivers 10040, and the staples 22030 supported thereon, toward the anvil 10060. In essence, thrtherto the above, the stapledrivers 10040 can move the staples 22030 from anunfired position (FIG. 10) to a fired position (FIGS. 11 and 12) wherein the staples 22030 can contact the anvil 10060 and be deformed between an undeformed configuration (FIG. 10) and a deformed configuration (FIGS. I I and i2). The anvil 10060 can comprise frmirin rockets 10062 which can be configured to receive and deform the staples 22030. Staples 22030 can be the same as or similar to staples 10030, for example and/or any other staples disclosed herein, and, as such, staples 22030 are not described in greater detail herein. The reader will note, however, that the staples 22030cancompriseanysuitableshapeand/orsuitabledimensions,suchaswidthand/orheight,forexamnpe,intheir undefored configuration andor their defored configuration. For instance, the staples 22030 can, in certain circumstances, comprise a heightwhich does not extend above a deck surface 22011 of the cartridge body 22010 when the staples 22030 are in their unfired positions while, in other circumstances, the staples 22030 can comprise a height in which the legs of the staples 22030 extend upwardly from the deck surface 22011 when the staples 22030 are in their unfired positionssuch that the esoftbestaiples 22030 are at least partially embeddedin a tissue thickness compensatory 22010 of the cartridge assembly 22000.

[0094] With continued reference to the embodiment depicted in FIGS, 9-12, further to the above, the cartridge assembly 22000 can comprise a cartridge body 22010 and a tissue thickness compensator 22020. In various circumstances, the cartridge body 22010 can be similar to the support portion 10010, for example, in many respects and, as a result, many of such respects are not repeated hereinl for the sake of brevity Furtlermore, the tissue thickness compensator 22020 can be similar to the tissue thickness comnpensator 10020, for example, in many respects. Further to the above, the firing member 10052 can includea cutting portion 10053 which can be configured to transect the tissue positioned between the anvil 10060 and the tissue thickness compensator 22020 as the firing member 10052 is advanceddistally. Invarious circumstances, as aresult, the firing member 10052 can be configured to concurrently fire the staples 22030 to staple the tissuefT and cut the tissue T. In certain circumstances, the firing process can at least partially lead thecutting process. Stated another way, the cuttingprocess can lag the firing process. In such circumstances, a portion ofthe tissueTcan be stapled and then incised.

[0095] As illustrated in FIGS 9-12, the cartridge bod'y 2010 can include a cartridge knife slot 22015 which can be configured to receive a portion of the firng member 10052 as thefiring member 10052 is advanced distally. Further to the above, the anvil 10060 can include an anvil knife slot 10065 whichcan be onfiguredtoreceiveaportionofthe firing member 10052 as the fringmember 10052 is advanced distally. In various circumstances, the tissue thickness compensator 22020 can comprise a tissue thickness compensatory nifeslot22025whic be alignedwiththeanvil knife slot 10065 and the cartridge knife slot 22015 such that the firing member 10052 can pass throughthe cartridge knife slot 22015, the anvil knife slot 10065, and the tissue thickness compensator knife slot 2025 simultaneously. In various circumstances, the anvil knife slot 10065 can extend over the tissue thickness copensator knife slot 22025 such that the cutting portion 10053 of the firingmember 10052 can pass through the cartridge knife slot 22015, the anvil knife slot 10065, and the tissue thickness compensator knife slot 22025 simultaneously. The tissue thickness conpensatorknife slot 22025 can define a tissue thickness compensatorknife path for the cutting portion 10053 wherein the tissue thickness compensator knife path can be parallel to the anvil knife path andthe cartridge knife path In various circumstances, the tissue thickness compensator knife path can be longitudinal while, in certain circumstances, the tissue thickness compensatorknife path can be curved, Furtherto theabove, curvedendeffectors and curved fastener cartridges are disclosed in U.S. Patent Application Publication No. 2008/0169329. Theentire disclosure ofU.S. PatentApcation SerialNoi 62164,entiedCURVED END EFFECTOR FOR A SURGICAL STAPLING DEVICE, filed on January 2007, now U.S. Patent Application Publication No. 2008/0169329, is hereby incorporated by reference herein. In suchcrcurnstances, a tissue thickness conpensator can be curved. In atleast one such embodiment, the tissue thickness compensator can be curved to match the curvature of the cartridge body of the fastener cartridge. Methods and techniques for modifying a tissue thickness compensator to include a knife slot such as, for example, the knife slot 22025 are described below.

[0096] Furtherto the above, referring primarilyto FIG. 9, the tissue thickness compensatorknife slot 22025 can extend between a firstsiapling portion 22021a which can bestapled byafitstgroupofstaples22030 and asecont staplingportion 22021b which can be stapledby a second group of staples 22030. The knife slot 22025 can releasably connect the first staplin portion 22021a tothe second stapling portion 22021b. In use, as illustrated in FIG, 9, the cutting portion 10053 can be advanced distally through the knife slot 22025 to transect the knife slot 22025 and separate the first stapling portion 22021 aand the second stapling portion 22021b. In certain circumstances, the knife slot 22025 can comprise a plurality of connectors, or bridges, 22026 which can connect the first stapling portion

22021a and the second stapling portion 22021b prior to being transected by the cutting portion 10053. In various circumstances, the connectors 22026 can have the sanmethickness asthe first staptling portion 22021a'and/or the second stapling- portion 22021b, at least when the tissue thickness compensator 22020 is in an unrcopressed state. In at least one such circumstance, the connectors 22026, the first stapting portion 22021a, and/or the second stapling portion 22021b can be unitarily and integrally formed froi a flat, or at least substantially flat, piece ofmaterial, for example. In various other circumstances, the first stapling portion 22021a can comprise afirst thickness, the second stapling portion 22021b can comprise a second thickness, andthe connectors 22026 can comprise a third thickness, wherein oneormoreofthe firstthicknesshesecond thickness, and the third thickness can be different than the other thicknesses.

[0097] The knife slot 22025 can further comprise apertures, such as apertures 22024, for example, defined therein. For instance, the apertures 22024 can be elongate and can extend longitudinally along the knife slot 22025. In various other circumstances, the apertures in the knife slot 22025 can comprise any suitable arrangement. In certain circumstances, the apertures 22024 can comprise perforations positioned intermediate the connectors 22026 which can be formed utilizing a laser cutting operation, for example. In some circumstances, the apertures 22024 can be cut from sheet of material to form the tissue thickness compensator 22020 such that the apertures 22024 and the connectors 22026 are arranged in an alternating arrangement, for example. In otherinstances, the tissue thickness compensator 22020 can be tuolded with aperries 22024 already formed therein. In various circumstances, one or more ofthe apertures 22024 can comprise through holes, for example. In various circumstances, one or more ofthe apertures 22024 can comprise clearance apertures, for example. In certain instances, one or more of the apertures 22024may not comprise through holes and may instead comprise reductions in the thickness of the knife slot 22025, for example. Methods and techniques for modifyinga tissuethickness cotpensator to include apertures such as, for example, the apertures 22024 are described below.

[0098] Further to the above, referring again to FIGS, 9- 1, patient tissue can be positioned intermediate the anvil 10060 of the end effector 22090 and the tissue thickness compensator 22020 ofthe cartridge assembly 22000 when the anvil 10060 is in an opert position. When the anvil 10060 is moved into a closed position, a bottom surface, or tissue-contacting surface, 10063 of the anvil 10060 can contact the tissue T and push thetissue T toward a deck surface 22011 ofthe cartridge body 22010. The tissue T can contact a top surface, or tissue contacting surface, 22021 of the tissue thickness compensator 22020 wherein, when the anvil 10060 is moved into its closed position, the anvil 10060 can press the tissue T against the tissue thickness conmpensator 22020 and, f-ther to the above, compress the tissue thickness compensator 22020 against the deck surface 22011 of the cartridge body 220 1 0. In various circumstances, the tissue thickness compensator 2020 can comprise a bottom surface 22029 which can abut the deck surface 22011. in some circumstances, a gap may be present between the bottom surface 22029 and the deck surface 22011 before the tissue thickness compensatory 22020 is compressed against the cartridge body 22010. In such circumstances, the tissue thickness compensator 22020 may first translate toward the cartridge body 22010 before being compressed thereagainst. When the tissue thickness compensator 22020 is compressed against the cartridge body 22010, in various circumstances, the first staying portion 22021a and/or the second. staping portion 22021b of the tissue thickness comnpensator 22020 may move laterally. For instance, the first stapling portion 22021a and/orthe second stapling portion 22021b may move laterally away from the cartridge knife slot 22015. Invarious circumstances, the connectors 22026 can be configured to inhibit such lateral movement betweentefrst stapling portion 22021a and the second stapling portion 22021b. In various circumstances, referringprimarily to FIG. 11, the connectors 22026 can be configured to stretch to permit some relative lateral movement between the First stapling portion 22021a and the second stapling portion 2202lb when the anvil 10060 is closed. In the event that the anvil 10060 is reopened, the connectors 22026 can be contigured to elastically return, or at least substantiallv return, to their unstretched configuration and, as a result, pull the first stapling portion22021a and the second stapling portion 2202lb laterally back toward their original positions, illustrated in FIG. 10. Moreover, the anvil 10060 can compress the tissueT when the anvil 10060 is moved into its closed position. In such circumstances, the tissue T may at least partially flow into the apertures 2202 4 . 100991 Upon reviewing FIGS. 10-12, the reader will appreciate that the knife slot 22025 of the tissue thickness compensator 22020 comprises less material along the longitudinal length thereofthan the first stapling portion 22021a and/or the second stapling portion 2202lb. Stated another way, a longitudinal cross-section through the first stapling portion 22021a and/or the second stapling portion 22021b would transect a first amount of material while a longitudinal cross-section through the knife slot 22025 would transect a second amount oftmaterial which is less than the first amount ofmaterial.

[0100] Once the anivil 10060 las been suitably positioned, further to the above, the firing member 10052 can be advanced distally to fire the staples, as illustrated in FIG. 11, and incise the tissue T andthe connectors 22026, as illustrated in FIG. 12 r Furhermiore, the tissue thickness compensator incision force, the tissue incision force, the tissue thickness compensator drag force, and/or the tissue drag force can dull the cutting portion 10053 of the firing member 10052. A dull knife tay not be able to transect the tissue'Tand/or the tissue thickness compensator 22020, for example, according to a preferred manner. With primary reference to FIG. 12, the cutting portion 10053 can comprise a first knife edge zone 10053a, a second knife edge zote 10053b, and/or a thirdkni fe edge zone 10053c, for example, wherein the first knife edge zone 10053a is positioned vertically aove the second knife edge zone 10053b, and wherein the second knife edge zone 100531) is positioned vertically above the third knife edge zone 10053c, for example. The cutting portion 10053 can comprise any suitable number andor location of knife edge zones wherein the knife ede zones depicted in FIG 12 have been selected for the purposes of discussion. Further to the above, the first knife edge zone 10053a can be configured to transect thetissueT while the secondknife edge zone 10053b can be configured to transect the tissueftickness compensator 22020. As a result, the first knife edge zone 10053a may experience thietissueincision force and/orthe tissue drag force discussed above. Such forces maywear ordull the first knife edge zone 10053a at a first rate. The second knife edge zone 10053b may experience the tissue thickness compensator incision force and/or the tissue thickness cotmpensator drag force discussed. above. Such forces may wear or dull the second knife edge zone 10053b at a second rate. In various circumstances, the second rate can be different than the first rate.

[0101] Turning now to FIGS. 13 and 14, a fastener cartridge 22400 can comprise atissue thickness comnpensator 22420 which can include a first stapling portion 2242aand a second stapling portion 2242lb which are connected by a knife slot 22425. The knife slot22425 can comprise an angled longitudinal connector 22426. The angled longitudinal connector 22426 can extend between a proximal end 22401 of the knife slot 22425 and a distal end 22402 of the knife slot 22425. In some circumstances, the angled longitudinal connector 22426 can extend the entire length of the knife slot 22425 while, in othercircumstances, the angled longitudinal connector 22426 can extend less than the iengthof the knife slot'22425. Tte angled longitudinal connector 22426 can extend between a top surface 22428 of the tissue thickness compensator 22420 and a bottom surface 22429 of the tissue thickness compensator 22420. In some circumstances, the angled longitudinal connector 22426 can extend the entire distance between the top surface 22428 and the bottom surface 22429 while, in other circumstances, te anglediongitudinal connector 22426 can extend less than the distance between the top surface 22428 and thelbottom surface 2429. In various circumstances, the proximal end ofthe longitudinal connector 22426 can extend from theto surface 22428 ofthetissuethickness compensator while the distal end of the longitudinal connector 22426 can extend from the bottom surface 22429. Alternatively, the distal end of the longitudinal connector 22426 can extend from the top surface 22428 of the tissue thickness compensator while the proximal end of the longitudinal connector 22426 can extend from the bottom surface22429. Invarious circumstances, the longitudinal connector 22426 can comprise athinbridge (i.e. less than the full thickness of the tissue thickness compensator 22420) or a series ofthin bridges thatjoin the first stapling portion 22421a which can be stapled by a first group of staples 22030 to the second stapling portion 22421b which can be stapled byasecond groupofstaples 22030,for example.Thesethin,angledbridges,and/orthelongitudinal connector22426, could distribute the wear across the second knife edge zone 10053b, rathertIan concentrating it on one Spot. Invarious circumstances, as a result, the wear occurring on the second knife edge zone 10053b may be equal to, or closer to being equal to, the wear occurring at thefirst knife edge zone 0053a,forexample.

[0102] Referring now to FIGS. 15-17, an exemplary tissue thickness compensator assembly 1000 may include a first layer 1002 and a second layer 1004 attachable to the firstlayer 1002. The tissue thickness compensator assembly 1000 can be utilized with a surgical instrument such as, forexample, the surgical instrument 8010 (FIG.1). In addition, the tissue thickness compensatory assembly 1000can be utilized in a similar mariner as and can replace thetissue thickness compensator 22020 of the cartridge assembly 22000 ofthe end effector 22090 (FIG. 9). For example, the second layer 1004 of the tissue thickness compensator assembly 1000 may include a first portion 1006 which can be positioned on the deck surface 22011 on a first side of the cartridge knife slot 22015 in a similar fashion to the first stapling portion 22021a and a second portion 1008 which can be positioned on the deck surface 22011 on a second side, opposite the first side, of the cartridge knife slot 22015 in a similar fashion to the second stapling portion 22021b (FIGS. 9-11). In various instances, the first portion 1006 and the second portion 1008 of the second layer 1004 can be spaced apart and may comprise a gap 1010 therebetween which can comprise a knife path forthe cutting portion 10053 of-the firing member 10052 and may extend at least partially over the cartridge knite slot 22015 when thetissue thickness compensator assembly 1000 is assembled with the cartridge end effector 22090. in certain instances, the first layer 1002 can be configured to couple the first portion 1006 and the second portion 1008 and extend at least partially over the gap 1010, as illustrated in FIG. 17, for example.

[0103] In use, tissue T can be captured between the anvil 10060 and a tissue contacting surface 101 of the first layer1002. As the firing member 10052 is advanced, a first group ofstaples 20030 ca be deployed to staple the first portion 1006 and a second group of staples can be deployed to staple the second portion 1008. The first and second groups of staples can be configured to penetrate through a first deck contacting surface 1007 and a second deck contacting surface 1009, respectively,of the second layer 1004, then through the tissue contacting surface 1012 ofthe first layer, and then through the captured tissue T to contact the pockets 10062 of the anvil 10060. Furthermore, the advancement of the firing member 10052 can cause the cutting portion 10053 to be advanced distally through the gap 1010 ofthe tissue thicknesscompensator assembly 1000. The cutting portion 10053 may transect the first laver 1002 while advancing through thegap 1010 thereby separating the first portion 1006 and the second portion 1008 ofthe second layer 1004.

[0104] Reftrring again to FIG. 17, the first layer 1002 ofthetissue thickness compensator assembly 1000 may comprise a first height il, the first portion 1006 of the second layer1004 may comprise a second height 12, and the second portion 1008 of the second layer 1004may comprise a thirdheight H3, In certain circumstances, as illustrated in FIG. 17, the second height112 and the third height H3 can be the same or substantially the same. Inother circumstances, the secondheight 112 can be different from the third height 13. In certain circumstances, the First height HI can be less than the second height 12 and/or the third height H3, as illustrated in FIG. 17. The firstlayer 1002 ofthe tissue thickness compensator assembly 1000 may comprise a first density, the First portion 1006 ofthe second layer 1004 may comprise a second density, andthe second portion 1008 of the second laver 1004 may comprise a third density. In certaincircumstances,as illustrated in FIG. 17, the second density and the third density cat be the same or substantially the same. in other circumstances, the second density can be different 'ro the third density and/or different from the first density of the first layer 1002. The material compositions ofthe first portion 1006 and the second portion 1008 canbe the same, or at least substantiallythe same. In othercircumstances, the material compositions of the first portion 1006 and the second portion 1008 can be different fiom each other and/or cat be different from the material composition of the first layer 1002.

[0105] As described above, repeated use of the cutting portion 10053 to cut tissue T and tissue thickness compensatory material may dull th cutting portion 10053. To slow thedulling process, it may be desirable to reduce the tissue thickniess compensator material that is cut bythe cutting portion 10053. An additional benefit can be a reduction in the forces needed to advance the firing member 10052 distall during a firing stroke. In order to reduce the dulling ofthe cutting portion 10053, the first layer 1002 cat be comprised, at least partially, ofa thin film, for example. In such circumstances, the first height H! can be significantly less than the second height 12 and the third height H3, as ilistrated in FIG. 17. In certain circumstances, the slayer 1002 may comprise a uniform, or substantially uniform, height therethrough as illustrated in FIG. 17. In other circumstances, a gap bridging portion 1014of the first layer 1002 may extend at least partially over the gap 1010 andmay be thinner than the remainder of the first layer 1002. The cutting portion 10053 may transect the gap bridging portion 1014 of the first laver 1002 while advancing through the gap 1010 between the First portion 1006 and the second portion 1008 of the second layer 1004 which may reduce the resistance experienced by the cutting portion 10053 and/or slow the dulling ofthe cutting portion 10053, In any event, the firstlayer 1002 can be configured to rinitain a coupling engagement with the first portion 1006 and the second portion 1008 of the second layer 1004 prior to being transected, and to present the cutting portion 10053 with a reduced resistance as thecutti1ng portion 10053 is advanced to transect the first layer 1002.

[0106] To urtherreduce the dulling ofthe cutting portion 10053 and/orreduce he resistance experienced by the cuttingportion 10053, thegap bridgingportion 1014nmay compriseaperforatedsegmnent 1016alongthe knife path defined by the gap 1010, as illustrated in FIG. 16. The perforated segment 1016 can include a plurality of perforations 1018which can be cut into the first layer 1002 ptiortoieassemblyvof the first ayer 1002o the second aer 1004, forexample. The perforations 1018 can reducethe interaction ctween the cuttingportion 10053 andthefirstlayer 1002 as the cutting ortion 10053 is advanced through the knife atidefined bythe gap 1010, which may slow the dulling of the cutting portion 10053 and/orreducethe resistance experienced bythe cutting portion 10053

[0107] In various circumstances, as described in greater detail below, thetissue thickness compensatory assembly 1000 can be comprised of one ormore biocompatible materials. In certain circumstance, the first layer 1002 can be comprised ofa biocompatiebuttressmaterial and/or plastic material, such as polydioxanone (PDS) and/or polyglycolic acid (PGA), for example, and the second layer 1004 can be comprised of abioabsorbabe foam material and/or a compressible haemostatic material, such as oxidized regeneratedcellulose (ORC) for example. In certain circumstances, thefirst layer 1002 can be a thin filmcomprising a bioabsorbable material such as polyglycolic acid (PGA) which is marketed under the trade name Vieripolylactic acid (PLA orPLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHiA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. In certain ciircumnstances, the first portion1006 and/or the second portion 1008 ofthe second layer 1004 can be comprised ofa ivophilized foam comprising polylacticacid (PLA) and'or polyglycolic acid (PGA), for example. In certain circumstances, the First portion 1006 and/or the second portion 1008 of the second layer 1004 can be comprised of biocompatible foam which may comprise a porous, open cell foam and/or a porous, closed cell foam.

[0108] Referring again to FIGS. 15 and 17, the first layer 1002 can be altleast partially disposed over the second. layer 1004 such that- tc secondlayer1004 may be positionedbetween the first layer 1002 and the deck surface 22011 (FIG. 9) when the tissue thickness comtpensator assembly 1000 is assembled with the end effector 22090 (FIG. 9). In other circumstances, the first layer 1002 car be positioned beneath the first portion 1006 and the second portion 1008 (notsho such that the first layer 1002maybe positioned between the second layer 1004and the deck surface 22011 (FIG. 9) when the tissue thickness compensator assembly 1000 is assembled with the end effector 22090 (FIG. 9). In any event, the first layer 1002 can beattached to a first contactig surface 1020of the first portion 1006 and a second contacting surface 1022 of the second portion 1008 ofthe second layer 1004. The first layer 1002 can be attached to the second layer 1004 via a thermal pressing process involving the application of heat and/oropressure, as described in greater detail below. In other circumstances, the first layer 1002 can be attached to the second layer 1004 by a biocompatible adhesive material such as a fibrin and/or protein hydrogen, for example. Other means for attaching the first layer 1002 tofie second layer 1004 are contemplated by he pesent disclosure.

[0109] Referring now to FIGS. 21 and 22, the first layer 1002 can be at least partially embedded into the first portion 1006 and/or the second portion 1008 of the second laver 1004. in such circumstances, the tissue thickness compensator assembly 1000 can be prepared using a mold 1024, for example, as illustrated in FIG. 21. Invanous stances, an organic solution comprising a polymer such as, for example, polylactic acid (PLA) aid/or polyglycolic acid (PGA) can be poured into the mold1024.The first layer 1002 can be immersed into the organic solution. As illustrated in FIG. 22, a central shelf 1026 and a central beam 1027 of a mold cover 1028 can trap the first layer 1002 therebetween to ensure that the first layer 1002 remains immersed in the organic solution which can then be lyophilized using conventional lyophilization techniques and/or any other suitable techniques, for example. Upon completion of the lyophilization process, and/or any other suitable process, the mold cover 1028 can be removed and the tissue thickness compensatory assembly 1000 can be recovered from the mold 1028.

[0110] As illustrated in FIG. 21, the first layer 1002 of the tissue thickness compensator 1000 can be partially positioned within the first portion 1006 and the second portion 1008 of the second layer 1004. In certain circumstances, the first layer 1002 can be partially positioned within one of the first portion 1006 and the second portion 1008 and attached to a top surface or a bottom surface ofthehoter one of the first portion 1006 and the second portion 1008. 101111 In certain circumstances, the central beam 1027 and the shelf 1026 can at least partially extend along an axis that is parallel or substantially parallel to the first deck contacting surface 1007 andor the second deck contacting surface 1009 when the cover 1028 is in a closed configuration with mold 1024, as illustrated in FIG. 22. In such crcrmstances, the first layer 1002 can be embedded into the first portion 1006 and/or the secondportion 1008 such that first layer 1002 is positioned or substantially positioned in a parallel or substantially parallel relationship with the first deck contacting surface 1007 and/or the second deck contacting surface 1009. In other circumstances, although not illustrated, the central beam 1027 and the shelf 1026 canat least partially extend along an axis that is at a oblique angle with the first deck contacting surface 1007 and/or the second deck contacting surface 1008 when the cover 1028 is ina closed configuration wit notd 1024. in such circumstances, the first layer 1002 can be embedded into the first portion 1006 and/or the second portion 1008 such that first layer 1002 is positioned or substantially positioned at an oblique angle with respect to the First deck contacting surface 1007 and/or the second deck contacting surface 1009. Other techniques for partially embedding the first layer 1002 intothefirst portion 1006 and/or the second potion 1008 are contemplated by tie present disclosure.

[0112] Referring now to FIGS. 18 and 19, a tissue thickness compensator assembly 1033, which is similarin many respects to the tissue thickness compensator assembly 1000 and the tissue thickness compensator 20020, is illustrated. The tissue thickness compensator assembly 1033 can comprise the first portion 1006 and the second portion 1008 which can be spaced apart and separably coupled together by a plurality of bridging members or connectors 1030 which may extend across the cap 1010 between the first portion 1006 and the second portion 1008. In addition, sone or all ofthe connectors 1030 ofthe tissue thickness compensator assembly 1033 can be partially embedded into the first portion 1006 and the second portion 1008, as illustrated in FIG. 19. Furtiemore, some or all ofthe connectors 1030 can comprise a first end positioned within the first portion 1006, a second end positioned within the second portion 1008, and a gap bridging portion 1032 therebetween. Te gap bridging portion 1032 may extend across the gap 1010 between the first portion 1006 and thesecond portion 1008, as illustrated in FIG. 19. The connectors 1030 can be spaced apart along the length of the gap 1010 to separably couple the first portion 1006 to the second portion 1008.

[0113] In certaincircumstances, the connectors 1030 can be evenly distributed alongat axis extending along the gap 1010, as illustrated in FIG. 19. In other circumstances, although not illustrated, the connectors 1030 can be unevenly distributed along the axis extending along thegap 1010. The cutting portion 10053 can be onfiguredto transect the gapbridging portions 1032 of the connectors 1030 as the cutting portion 10053 is advanced between the first portion 1006 and the second portion 1008 through the knife path defined bythe gap 1010.Where the connectors 1030 are uneveniv distributed alonethe axis extending along the first portion 1006 and the second portion, in at least one instance, the connectors 1030 can be disposed in greater frequency and/or in closer proximity to each other at a distal segment of the gap 1010 than at a proximal segment of the gap 1010 such that the cutting portion 10053 tay experience an increasing resistance as it is advanced along the knife path defined by the gap 1010. In other circumstances, the connectors 1030 can be disposed in greater frequency and/or in closer proximity to each other at a proximal segment of the gap 1010 than at a distal segment ofthe gap 1010 such thatthe cutting portion 10053 may experience a decreasing resistance as it is advanced along the knife path defined by the gap 1010, for example. 101141 In certain circumstances,the connectors 1030 can extend or substantially extend in a single plane which can be parallel or substantially parallel to the first deck contacting portion 1007 and/or the second deck contacting portion 1009, as illustrated in FIG. 19. In other circumstances, although not illustrated, the connectors 1030 can extend or substantially extend along a plurality of planes which cart be parallel or substantially parallel to each other and/or to the first deck contacting portion 1007 and/orthe second deck contacting portion 1009.

[0115] Further to the above, some or all ofthe gap bridging portions 1032 of the connectors 1030 can be thinner than the remainder of their respective connectors 1030 to present tile cutting portion 10053 with reduced resistance as the cutting portion 10053 is advanced to transect the connectors 1030 while maintaining acoupling engagement with the First portion 1006 and the second portion 1008 ofthe second layer 1004. For example, sone or all the connectors 1030 can comprise a dog-bone shape with thicker ends terninating within the first portion 1006 and the second portion 1008 of the second layer 1004 and thinner central portions extending therebetween. In certain circumstances, the connectors 1030 can each be comprised of a piece of suture which may be omprised of bioabsorbable material such as polyglycolic acid (PGA) which is marketed under the trade name Vieryl, polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monoervi, polycaprolactone (PC),andor a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example.

[0116] Referring again to FIG. 18, the tissue thickness compensator assembly 1033 can be prepared using amold 1034. An organic solutioncomprising a polymer such as, for example, polylactic acid (PLA) and/or polyglycolic acid (PGA) can be poured into the mold 1034. The connectors 1030 can be immersed into the organic solution. As illustrated in FIG. 18, one ormore of the onnectors 1030 can each be trapped in one or more dedicated slots 1040 on a central shelf 10361by one or moreobeams 1039 extending from a mold cover 1038 andconfigured for mating engagetnent with the slots 1040 when themold cover 1038 is in a closed confiiuration with the mold 1034 to ensure that theconnectors 1030 remain immersed in the organic solution. The slots 1040 can be sized to receive or at least partially receive the bridging portions 1032 which can be secured by the beams 1039 when themold cover 1038 is in the closed configuration with the mold 1034. The ends of the connectors 1030 extending from the gap bridging portions 1032 may freely floatinthe organic solution.Alternatively, the ends of the connectors 1030 car be secured to sides of the mold 1034, for example. In certain circumstances, the connectors 1030 can be stretched in the organic solution between the sidesof the mold 1034. In other circumstances, the connectors 1030 canbe loosely held between the sides of the mold 1034 to extendthrough the organic solution ina non-linear fashion, for example

[0117] Further tothe above,in various instances,theorganicsolution can then belyophilizedusing convention iyophilization techniques and/or any other suitable techniques. Upon completion ofthe lyophilizationprocess, the mold cover 1036 can be removed and the tissuethickness compensator assembly 1033 can be recovered from the mold 1034. As illustrated in FIG. 19, the resulting tissue thickness compensatory assembly 1033 includes connectors 1030 partially positioned within the first portion 1006 and the second portion 1008. Other techniques for partially embedding the connectors 1030 into the first portion 1006 and/or the second portion 1008 are contemplated by the present disclosure. The reader will appreciate that the connectors 1030 can be positioned closer to or further away from the deckcontacting surfaces 1007 and 1009 by changing the height of the central shelf 1038 and/or depth of the slots 1040.

[0118] Referring now to FIG. 20, a tissue thickness compensator assembly 1042, which may be similar in many assembly respects to the tissue thickness compensator assembly 1033, the tissue thickness compensator 1000, and/or the tissue thickness compensatory 20020, is illustrated. The tissue thickness compensator assembly 1042 may comprise the first portion 1006 and the second portion 1008 which can be spaced apart and separably coupled together by a continuous flexible member 1044 which may form a plurality of bridging members or connectors 1046 which may extend across the gap 1010 between the first portion 1006 and the second portion 1008. The continuous flexible member 1044 may include a first end 1048, a second end 1050, and a flexible portion 1052 extendingbetween the first end 1048 and the second end 1050. The flexble portion 1052 can be configured to extend through the first portion 1006 and the second portion 1008 several times, for example in a zigzag pattern, to form the connectors 1046, as illustrated in FIG. 20. The flexible potion 1052 car be passed in a first direction through a distal segment 1054 of the first portion 1006 and a distal segment 1056 of the second portion 1008 to form a first gap bridging portion 046a across the gap 1010. The exile portion 1052 can then be looped and passed in a second direction, opposite the first direction, through the second portion 1008 poximal to the distal segment 1056 and through the first portion 1006 proximal to the distal segment 1054 thereby forming a second gap bridging portion 1046b proxiial the first gap bridging portion 1046a. Additional gap bridging portions 1046c and 1046d, for example, can be formed in the same manner acrossthe gap. 1010, as iustraed in FIG 20.

[0119] In certain circumstances, the continuous flexible member 1044 can comprise a suture and can be comprised of a suture material such as polvglycolic acid (PGA) which is marketed under the trade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyakanoate (PHA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monocryl, polycaprolactone (PCLI), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. In certain circumstances, the tissue thickness compensatorassembly 1042 can be assembled after the first portion 1006 and the second portion 1008 aremanufactured, for example, vialyophilization. In some circumstances, a eedle (not shown) can be attacledto the fist end 1048 of the tionus exibleitemnber 1044 and can be passed through the first portion 1006 and the second portion 1008, for example in a zigzag pattern, to couple the first portion 1006 to the second portion 1008, as described above. The first end 1048 atd/or the second end 1050 of the continuous flexible number 1044 can be secured to the side walls of the first portion 1006 and/or the second portion 1008 bytying in one or more knots at the first end 1048 and/or the second end1050,for example. The knots may abut against the side walls of le first portion 1006 and/or the second portion 1008 to prevent the flexible portion 1052 from unraveling relative to the first portion 1006 and/or the second portion 1008. In other circumstances, the first portion 1006 and the second portion 1008 o- the tissue thickness compensator assembly 1042 can be formed around the continuous flexible menmer 1044. In such circumstances, asillustratedin FIG. 20, the continuous flexible member 1044 can be disposed in a mold 1062, for example in a zigzag pattern, with slots 1064 defined sidewalls 1066 and slots 1068 defined in central shelf 1070. An organic solution comprising a polymer such as, for example, polylactic acid (PLA) and/or polyglycolic acid (PGA)can be poured into the mold 1062 until the continuous flexible member 1044 is immersed in the organic solution. A mold cover 1072 can be used to ensure thatthe cotinuous flexible member 1044 remains immersed in the organic solution which can then be lyophilized usingconventional lyophilization techniques and/or any other suitable techniques. The first end 1048 and the second end 1050 ofthe continuous flexible member 1044 can be secured at openings 1053 and 1055 of the mold 1062, respectively, by tying ione ormore knots atthe first end 1048 and the second end 1050 after passing the first end 1048 through the opening 1053 and the secondend 1050 throughthe opening 1055, forexample. The knots may abut against-the side walls ofthe mold 1062 to prevent the continuous flexible member 1044 frornunraveling relative to tae mold 1066. After the tissue thickness compensatory has been removed from the mold, in various instances, portions ofthe continuous flexible tiember 1044, such as portions 1048, 1050, and/or 1052, for example, can then be cut and removed from the tissue thickness compensator. Other techniques for assembling the tissue thicknesscomnpensator assembly 1042 are contempateby the present disclosure

[0120] In certain circumstances, atissue thickness compensator assembly such as, forexample, the tissue thickness compensator assembly 1042 can be comprotnised when excessive force or pressures applied thereto. For instance, pressure can be applied to a tissue thickness compensator assembly such as, for example, the tissue thickness compensator assemblyt1042 when the tissue thickness compensator assembly 1042 is loaded onto a staple cartridge such as, for example,the staple cartridge 10000.The tissue thickness compensator assembly 1042 can be equipped with a pressure or force sensitive member that can provide a user with a warning feedback if the pressure experienced by the tissue thickness compensator assembly exceeds a threshold. For example, a pressure or force sensitive film can be attached to the tissue thickness compensator assembly 1042 and can be configured to change color upon experiencing pressure that exceeds the threshold. In certain circumstances, the pressure or force sensitive film can be disposed over the first portion 1006 and/or the second portion 1008 and can be attached thereto via an adhesive, for example.The pressure or force sensitive film can be biocompatible to permit implantation ofthe pressure or force sensitive film with the tissue thickness compensator assembly 1042 inside a patient.

[0121] Referring now to FIGS. 23-25, a surgical end effectr1100 is illustrated. The end effector 1100 is similar in many respects to various end effectors disclosed elsewhere herein such as, for example, the end efector 22090 (FIG. 9). As illustrated in FIG. 23, the end-effector 1100 can include a staple cartridge assembly 1102 which is similar in many respectstothestaplcartridge assembly 20200 (FIG. 6), forexample. In addition, the endeffector 1100 may include a tissue thickness compensator 1104 which is similar in many respects to other tissuethickness coipensators disclose elsewhere in this document such as the tissue thickness compensator 22020 (FIG. 9), the tissue thickness compensator 20220 (FIG. 6), and/or the tissue thickness compensator 10020 (FIG. 4), for example.

[0122] Furthertothe above, end effector 1100 can include atissuethickness compensator 1104whereinthe tissue thickness compensator 1104 can be prepared using conventional lyophilization techniques and/or any other suitable techniques. In at least one example, the tissue thickness compensator 1104 can be prepared by dissolving apolymer such as, for example, polylactic acid (PLA)and/or polyglycolic acid (PGA) in an organic solvent and lyophilizirig the solution. The tissue thickness compensator 1104 can be comprised of a biocompatible foam which may comprise a

porous, open cell foam and/or a porous, closed cellfoam, for example.

[0123] Further to the above, the tissue thickness compensator 1104 can be altered or modified for usein a surgical procedure. For example, upon completion of the lyophilization process, the tissue thickness conperisator 1104 can be contacted with a modifying member 1106 tomodify thetissuethickness compensator 1104 forusein particular surgical procedure. In certain circumstances, the modification can occur after assembling the tissue thickness compensator 1104 with the end effector 1100, as illustratedin FIGS. 23-35 For example, as illustrated in FIG. 23,the tissue thickness compensator 1104 can be releasably assembled to the cartridgeassenbly 1102 and modified while assembled withthe cartridge assembly 1102. In other circumstances, the modification can occur before assemblin the tissue thickness comnpensator 1104 with the end effector 1100. In at least oneexample, themodification can be perfonned as a separate step during manufacturing. In yet another example, themodification may be performed during a surgical procedure.

[01241 As described in greater detail below, themodification process can involve modifyinga surface oraplurality of surfaces ofthe tissue thickness compensator 1104. In certain circumstances, the modification process can involve modifying one or more portions of the tissue thickness compensator 1104 One or more portions can be modified ina single modification process. Alternatively, a plurality of portions can eachbe modified separately consecutive modification processes. In certain circumstances, the modification process can comprise a thermal pressingprocess which can be used to change the shape, size, dimensions, and/or porosity of at least a portion ofthe tissue thickness compensator 1104. Furthermore, themodifications process can include means for creating space within one or more portions of the tissue thickness compensator 1104.

[0125] Reterring again to FIGS. 23-25, in certain circumstances, a portion 1107 (FIG. 23) of the tissue thickness compensator 1104 can be modified by a thenal pressing process which may include transitioning the portion 1107 to a glassy state, engaging the portion 1107 with the modifying member 1106, applying pressure onto the portion 1107 whileit is in the glassy state, and allowing the portion 1107 to cool below the glassy state while the modifying member1106 is still engaged with the portion 1107. The modifying member 1106 may be used tomaintain the pressure on the portion 1107 for a time period sufficient to create the resulting modified portion 1108 (FIG. 25). It is note worthy that a material's transition into a glassy state can be a reversible transition from a relatively hard state to a relatively molten or flexibe state in response to an increase in the temperature of the material to a lass transiton temnperature. A glass transition temperature ofthe material can be a particular temperatueor, in some instances, a range of temperatures. lbe tissue thickness compensator modification process described herein takes advantage ofthis phenomenon by modifying a tissue thickness comnpensator while thetissue thickness compensator is in the glassy flexible state and then allowing the tissue thickness compensator to cool below the glass transition temperature while maintaining the modihiation.

[0126] Furthertotheabove,referringagaintoFIGS. 2 3-25 tbeportion1107ofthetissuethicknesscompensator 1004 can be ttnsitioned into the glassy state by heating atleast the portion 107 to a temperature greater than or equal to a glass transition temperature of the material from which the portion 1 107 is composed but lower than the melting temperature of the same. For example, the tissue thickness compensator 1104 can be comprised ofpolyglycolic acid (PGA) and in such circumstances, the portion 1107 can be transitioned into the glassy state by heating the portion 1107 to a temperature that is greater than or equal to the glass transition terature of polyglycolic acid (PGA) but lowerthan the melting temerature ofthe same. In various instances, the glass transition temperature ofpolyglycolic acid (PGA) cart be in the range of35-40 °C, for example, and its meltig temperature cma be in the range of"225-230 C, for example. In at least one example, the portion 1107 of the tissue thickness compensator 1104 can be heated to a temperature that is greater than or equal to 35 °C but lower that 225 °C in order to transition the portion 1107 to the glassy state. In another example, the portion 1107 can be transitioned to the glassy state by heating the portion 1107 to a temperature that is greater than or equal to 40 °Cbut lower tha 200 °C, for example. 101271 Futther to the above, the modifying member 1106 can then be used to apply pressure onto the portion 1107 while the portion 1107 is in theglassy state. The portion 1107 can be allowed to exit the glassy state by cooling the portion 1 107 to a temperature below 35 °C, for example. The pressure tay be maintained for a tiie period sufficient to permit the tissue thickness compensator 1104 to retain, or at least partially retain, themodification imposed by the todifyingimember 1106.

[0128] In certain examples, the pressure can be maintained for a period oftime from about 30 seconds to about 8 hours, for example, during the tite in the glassy stateand/or for a period oftime from about 30 seconds to about 8 hours, for example, after exiting the glassy state. In at least one example, the pressure can be maintained for approximately 10 minutes during the time in the glassy state and forapproximately 10min tes afterexiitigthe glassy state. Other time periods for maintaining the pressure are contemplated by the present disclosure.

[0129] In certain circumstances, the modifying member 1106 can be used to apply pressure onto the portion 1107 before the portion 1107 istransitioned to the glassy state. In certain circumstances, the modifying member 1106 may apply pressure to the portion 1107 while the Portion 1107 is heated to reach the glassy state, while the portion 1107 is in the glassy state, and/or whilethe portion 1107 is transitioned or cooled to a temperature below the glassy state. In certain circumstances, the pressure applied to the portion 1107 can be gradually increased toward a threshold as the temperature of the portion 1107 is gradually increased to transition the portion 1107 toward the glassy state, for example. In certain circumstances, the pressure applied to the portion 1107 can be removed, gradually removed, or at leastpartially reduced as the portion 107 exits the glassy state, before the portion 1107 exits the glassy state, and/or

after the portion i 107 exits the glassy state.

[01301 In certain circumstances, the modifying member 1106 can also be a heat sourcefor transitioning the portion 1107 ofthe tissue thickness compensatory i 104 to the glassy state. For example, the modifying member 1106 can comprise acylindrical distal portion 1 10, as illustrated in FIG. 24,wuhich may include aheating coil (not shown). A user can may energize the heating coil and engage the portion 1107 ofthe tissue thickness compensator 1104 with the modifying member 1106 toheat the portion 1107 to a temperature that is greater than or equal theglasstransition temperature of the material composition oftheporion :07. Upon reaching adesired temperature, themodifYing member may be pressed against the portion 1107, as illustrated in FIG. 24. Alternatively, the modifying member may be pressed against lie portion 1107 before the modifying member 1106 reaches the desired temperature. As described above, the pressure may be maintained for a time period sufficient to permit the tissue thickness compensator 1104 to retain, or at least partially retain, the modification imposed by the modifying member 1106. In addition, the heating coil ofthe modifying member 1106 canbeturnedoff to allowthe temperature oftheportion 1107 to cool below the glass transition temperature. The modifyingrmebrcan thenbe removed. Incertain circumstances, thepressure applied by the modifying member 1106 can beinitiated prior tothe portion 1107 entering the glassy state and maintained throughout the glassy state, In sone circumstances, the pressure applied by the rnodifyin eirber 1106 can be removed while the portion 1107 is in the glassy state.

[0131] As illustrated in FIGS. 23-25, the nodif'ingmember 1106 can be configured to change the shape, size, dimensions, density, spring rate, aid/or porosity of the portion 1107 ofthe tissue thickness compensator 1104. For

example, the modified tion comprise a substantially cocave top surface 1114 with a reduced height H1, 1108 pormay while the remainder of the tissue thickness compensator 1104 may retain a substantially flat top surface incudiig an original height H which is greater than the reduced height H, as illustrated in FIG. 25. As described above, the miodifyirg member 1106 may comprise acylindrical distal portion 1110, In such circumstances, the curvature ofthe resulting concave surface 1114 can, in part, depend on the curvature of the cylindrical distal portion 1110 of the modifying member 1106 in contact with the portion 1107 of the tissue thicimess compensator 1104 during the modincation process. Furthermore, the modined portion 1108 may posss a new lower porosity compared to the

unmodified portion 1107 which canresult, at least in part, from the conpressive forces applied to tle portion 1107 by the moditing member 1106 during the modification process, as described above. Said another way, the pressure applied to the portion 1107 during theiodification process may yield a material redistribution wherein a cross-section through the modified portion 1108 may comprise a greater material density thana similar cross section through the portion 1107, prior to the nodification process. Furthermore, themodified portion 1108 may comprise a different spring rate from the remainder of the tissue thickness compensatory 1104 which can result, in part, from the changes in density and porosity realized by the modified portion 1108 during the modification process, as described in greater detail below. In at least one instance, the spring rate ofthe modified portion 1108 may be less than or greater than the spring rate ofthe unmodinFied portion 1107. 101321 Referriig now to FIGS. 26-34, a tissue thickiess compensator can be modified prior to assembly with aneiid effector such as, for example, the end effector 22090 (FIG.9). In certain circumstances, as illustrated in FIGS. 27, 30, asnd33,a mold can beutilized tomodifyatissue thicknesscompenmsatorusing a thermal pressingeprocess,asdescribed above. For example, as illustrated in FIGS. 26-28, a tissue thickess comnpensator 1120 can be modified to include a longitudinalslot 1122. The tissue thickness compensatory 1120ay be similar inmany respects to othertissue thickness compensators described elsewhere such as, forexample, the tissue thickness compensatory 22020 (FIG. 9). For example, like the compensatory 22020, the coipensator 1120 can be utilized wit the end effector 22090. Furthermore, the longitudinal slot 1122 may be similar in many respects to the knife slot 22025. For example, like the knife slot22025, the slot 1122 may define a tissue thickness compensator knife path for the cutting portion 10053 between a first stapling portion 1124a aid a second stapling portion 1124b, Furtherore, te first stapling portion I124a and the second stapling portion 1124b can be similar in many respects to the first stapling portion 22021a (FIG. 9) and the second stapling portion 22021b (FIG. 9), respectively, of the tissue thickness compensator 22020. in addition, the slot 1122 can be configured to releasably connect the first stapling portion 1124a and the second stapling portion 1124b such that, in use with the end effiector 22090, the cutting portion 10053 can be advanced distally through the slot 1122 to transect the slot 1122 and separatethe first stapling portion 1124a and the second stapling portion i 124b

[0133] Referring again to FIGS. 26-28, the tissue thickness compensator 1120 can be prepared using traditional lyophilization techniques and/or any other suitable techniques. In addition, the tissue thickness compensatory 1120 can be modified oraltered to create the slot 1122 therethrough. Similarto the tissue thickness compensator 1104, the tissue thickness compensatory 1120 can be comprised at least in part of a material comprising a glass transition temperature and can modified bytransitioningthe material into a glassy state. In one example, the tissue thickness compensator 1 120 canbe heated in an oven (not shown) to a temperature greater than or equal to the glass transition temperature of the material composition of the tissue thickness compensator 1120 but less tha the melting temperature of the same. A mold 1126 comprisinga central beam 1128, as illustrated in FIG. 27, can be utilized to create the slot 1122 by inserting the central beami1128 into the tissue thickness compensator 1120 while the tissue thickness compensator 1120 is in the glassy state. The tissue thickness compensator 1120 can then be allowed to cool to a temperature below the glasstransition temperature while the central beam 1128remainsinserted into the tissue thickness compensator 1120. In some instances, the central beam 1128 can be removed from the tissue thickness compensator 1120 while the tissue thickness compensator1120is in its glassy state.

[0134] In certain circumstances, a cooling medium can be utilized to actively cool the tissue thicknesscompensator 1120. In some instances, a fan can be used to generate a flow of air over the tissue thickness comensator 1120 while the tissue thickness compensator 1120 is in the mold 1126 and/or after the tissue thickness compensator 1120 has been removed from the nold. In some instances, a refrigeration process can beutilized to cool the tissue thickness compensator 1120 while the tissue thickness compensator 1120 is in the mold 1126 and/or after thetissue thickness compensator 1120 has been removed from the nold. The centralbeam 1128 can be removed after transitioning the tissue thickness compensator 1120 out of the glassy state. The central beam 1128 can remain inserted into the tissue thickness compensator 1120 for a time period sufficient to permit the tissue thickness compensator 1120 to retain, or at east substantially retain, the space occupied by the central beam 1128. In certain examples, the central beam 1128 can remain inserted for a period oftime from about 30 seconds to about 8 hours, for example, during the time in the glassy state and/or for a period of time from about 30 seconds to about 8 hours, for example, after exiting he glassy state. Inat least one example, the central beam 1128 can remain inserted for approximately 10 minutes during the time inhe glassy state and for approximately 10 minutes after exiting the glassy state. Other time periods t ormaitining the central beam 1128 within the tissue thickness compensator 1120 are contemplated by the present disclosure.

[0135] Further to the above, as illustrated in FIG. 28, pressure applied by the central beim 1128 during the modification process may yield an increased material density at a portion 1130 of the tissue thickness compensator

1120. The portion 1130 may connect the first stapling portion 1124a and a second stapling portion 1124b thereby providing additional stability for the slot i 122. In certain circumstances, themold 1 126may comprise edgemodifiers such as, for examipe, edge modifiers 1132a and I132b which can modify the tissue thickness compensator 1120 during the iodication process to produce modified edges 1134a and. 1134b, respectively, as illustrated in FIG 28.

[0136] Referring again to FIGS. 26-28, it maybe desirable to remove a significant amount ofmaterial from the tissue thickness compensator 1120 to create the slot 1122. In such circumstances, the central beam 1128 can be heated to a temperature greater that the melting temperature ofthe material composition of the tissue thickness compensator 1120. Upon inserting the heated central beami 128 into thetissue tuickness compensator 1120, the central beam 1128 may melt through the tissue thickness compensator 1120 thereby creating a space for the slot 1122 within the tissue thickness compensator 1120, as illustrated in FIG, 28. Incertain circumstances, it may be desirable to gradually increase the pressure applied by the central beam 1128 against the tissue thickness compensator 1120to gradually insert the central beam 1128 into the tissue thickness compensator 1120.

[0137] in certain circumstances, it can be desirable to increase material density of one or more surfaces of a tissue thicknesscompensator. As illustrated in FIGS. 29-31, a tissue thickness compensator i140 can be modified or altered suchthat a surface 1142 of the tissue thickness compensator 1140 may comprise a higher material density than the remainder of the tissue thickness compensator 1140, which can be achieved, in certain circumstances, post iyophilization 'The tissue thickness copensator 1140 may be similar in rany respects to other tissue thickness compensators described elsewhere such as, for example, the tissue thickness compensator 22020 (FIG. 9) and/orthe tissue thickness comnensator 1120 (FIG. 26) A surface modifier 1144 cartbe utilized to modify the surface 1142 of the tissue thickness compensator 1140 using a thermal pressing process which is similar in many respects to the thermal pressing processes used to odify the tissuethickness compensator 1104 and/or the tissue thickness compensator 1120, as described above. For example, the tissue thickness compensatory 1140 can be comprised at least

in part of a material comprising a glass transition temperature adcan bemodified after being transitioned into a glassy state.

[0138] As described above, a tissue thickness compensator such as, for example, the tissue thickness compensator 1140 can be transitioned to the glassy state where it is heated to a temperature greater than or equal to the glass transition temperature ofthe material composition of the tissue thickness compensator 1140 but less than them ti temperature ofthe same. The surface modifier 1144 can be pressed agaitist the surface 1142 while the tissue thickness compensator 1140 is in the glassy state. The pressure applied by the surface modifier 1144 may compress the surface 1142 thereby increasing the material density of the surface 1142. The increase in material density can be retained by the surface i142 by allowing the surface i142 to cool to a temperature below the glass transition temperature.

[0139] i certain instances, the pressure applied by the surface modifier 1144 aainist the surface 1142 can be maintained otr a period of time from about 30 seconds to about 8 hours, for example, during the time in theglassy state and/fo r aperiod of time frotabout 30 seconds to about 8 hours, for example, after exiting the glassy state. In at least one examupe, the pressure can he maintained for approximately 10 minutes during the time in the glassy state and for pproxinately 10 minutes after exiting the glassy state. Other time periods formaintaining the pressure applied by the surface modifier 1144 against the surface 1142 are contemplated by the present disclosure.

[0140] In someinstances, a fan can be used to generate a flow of air over the tissue thickness compensator 1140 while the tissue thickness compensator 1140 is in contactwith themodifier 1144 and/or after the tissue thickness compensator 1140has been removed from the modifier 1144. Incmeinstances,a rfrieration process can be uttilized totoothe tissue thickness compensator1140whilelihe tssne thickness compensator 1140 isin contact with the modcfier 1144 and/or after the tissue thickness compensator 140 has been removed from the modifier 1144.

IUpon transitioning the tissue thickness compensator 1140 out of the glassy state, in various instances, the surface modifier 1144 can be disengaged from the tissue thickness compensator 1140. In certain circumstances, the surface modifier 1144 canincludea heatingelementwhichcanbeutilizedto increase the temperature of the surface 1142 toa temperature greater than or equal to the glass transition temperature ofthe material composition ofthetissue thiickess compensator 1140, as described above, 101411 Referringagain to FIG. 30, the surfacemodifier 1144maycomnrise a flat, oratleastsubstantially flat, contacting surface I 146 forcontacting the surface 1142, for example In other circumstances, the contacting surface 1146 may comprise various textures such as, for example, protrusions which can extend into the surface 1142 of the tissue thickness compensator 1140 during the modification process. In certain circumstances, the surface modifier 1144 can be used to apply pressure onto the surface 1142 ofthe tissue thickness compensator 1140 beforethetissue thickness compensator 1140 is transitioned to theglassy state. In certain circumstances, the surface modifier 1144 may apply pressure tothe surface 1142 whilethe tissue thickness cotupensator 1140isheated toreach theglassy state, whilethe tissue thickness compensatory 1140 is in theglassy state, and/owhlethetissuethicknesscompensator 1140 istransitioned or cooled to a temperature below the glassy state, It certain circutstances, the pressure applied by the surface modifier 1144 to the surface 1142 can be gradually increased toward a threshold as the temperature ofthe tissue thickness conpensator 1140 is gradually increased to transition the tissue thickness compensator 1140 toward the glassy state, for example. In certain circumstances, the pressure applied to the surface 1142 can be removed, gradually removed,orat least partially reduced as the tissue thickness compensator 1140 exits the glassy state, before

the tissue thickiess compensator 1140 exits the glassy state, and/or after the tissue thickness compensator 1140 exits the glassy state. 101421 In certain circumstances, the tissue thickness compensator 1140 can be modified or altered to include a skin or a dense outer layer. In certain circumstances, the resulting skin or denseouter layer may comprise textures such as, for example, protrusions which canxtend into the surface 1142 ofthetissue thiciess compensator 1140. In certain instances, the contacting surface 1 146 of the surface modifier 1144 can be heated to a temperature greater than or equal to the melting temperature ofthe material composition ofthe tissue thickness compensator 1140. The surface modifier 1144 and/or the tissue thickness compensator 140 can be moved tobring the surface 1142 of the tissue thickness compensator 1140 into contact with the heated contacting surface 1146 of the surface modifier 1144 thereby melting, or at least substantially melting, the surface 1142. The surface modifier 1144 and the tissue thickness compensator 1140 can then be separated to permit the modified surface 1142 to cool below its melting temperature which may create a skin or a dense outer layer onto the tissue thickness compensator 1140.

[0143] Incertaininstances,thecontactingsmface1146ofthesurfacemodifier1144canbeheatedprior t coming n contact with the surface 1142. in other instances, the contacting surface 1146 of the surfacemodifier 1144 ca be heated after coming in contact with the surface 1142.

[01441 In certain instances, the contacting surface 1146 of the surface modifier 1144 can remaining contact with the surface 1142 ofthe tissue thickness compensator 1140 for a time period sufficient to allow the surface 1142 to flow into a desired geometry. Such a time period can range from about 30 seconds toabout 8 hours, for example; other time periods are contemplated bythe present disclosure. Such a tie period can be sufficient to locally affectand/ormelt the materialofthe tissue thickness compensatory i140 and have it flow into a new geometry. As described herein, such a new geometry can be prescribed by the tooling used to makethe tissue thickness compensator 1140.

[0145] In certain instances, the surface 1142 of the tissue thickness compensator 1140 can be allowed to cool, or can be actively cooled, to a temperature below the melting temperature ofthe tissue thickness compensator 1140 before separating the surface modiftier 1144 from the tissue thickness compensatory 1140. Inother instances, the surface 142 of the tissue thickness comoensator 1140 can be allowed to cool, or can be actively cooled, to a temperature below the meltng temperature of the tissue thickness compensator 1140 after separating the surace iodifier1144 from the tissue thickness compensatory 1140.

[0146] Further to the above, the modified surface 1142 can comprise a density which is approximately 10% greater than the density of te remnainder ofthe tissue thickness compensator 1140, approximately 20% greater than the density of the remainder of the tissue thickness compensator 1140, approximately 30% greater than the density of the retnainder of the tissue thickness compensator 1140, approxiately 40% greater that the density of the reinainder of the tissue thickness cotnpensator 1140, approximately 50% greater than the density of the remainder of thetissue thickness compensator 1140, approximately 60% greater thanthe density of the remainder of le tissuethickness compensator 1140, approximately 70% greaterthan the density of the remainder of the tissue thickness compensator 1140, approximnately 80% greater tha the density of the remainder of the tissue thickness compensatory 1140, approximately 90% greater than the density of the remainder ofthe tissuethickness compensatory 1140, and/or approximately 100%greater than the density of the remainder of the tissue thickness comnpensator 1140, forexample. In various circumstances, the modified surface 1142 can comprise a density which is more than tie density of the remainder of the tissue thickness compensator 1140 and less than twice the density of the remainder ofthe tissue thickness compensator 1140, for example. In various circumstances, the modified surface 1142 can comprise a density which is over twice the density of the remaider ofthetissue thickness compensator 1140, for example. 101471 Referring now to FIGS. 32-34, atissue thickness compensator 1150 can be modified to include a plurality of apertures 1152 which may extend at cast partial through the tissue thickness compensator 1150. The tissue thickness comnpeisator 1150 imay be simiar in many respects to other tissue thickness comupensators described herein such as, for example, the tissue thickness compensator 20220 (FIG. 6). Like the compensator 20220, the compensator 1150 can be utilized with the cartridge assembly 20200 (FIG. 6) andthe apertures 1152 may be similar in many respects to tie earance apertures 20224 extending at least partially through the tissue thickness compensator 20220. For example, like the apertures 20224, the apertures 1152 ca be aligned with corresponding staple legs 20232 (FIG. 7)when the tissue thickness compensator 1150 is assembled with the cartidge assembly 20200 such that the staple legs20232 may move throughthe clearance apertures 1152in thetissue thickness compensator 1150 when the staple legs 2023 move from the unfired configuration to the fired configuration, as described above in greater detail.

[0148] Furtherto the above, referring again to FIGS. 32-34, thetissuethickness compensator 1150 canbe prepared usigi traditional lyophilization techniques and/or any other suitable techniques. In certain circumstances, a polymer having a glass transition temperature such as, for example, polylactic acid (PLA) and/or polyglycolic acid (PGA) can be dissolved in an organic solvent toform a solutionwhich can be yophilized to produce the tissue thickness compensator 1150. Furthermore, thetissue thickness compensator 1150 can be modified postlyophilizationusing a thermal pressing process which is similar in many respects to the thermal pressing processes used to modify the tissue thickness compensator 1104, the tissue thickness compensator 1120,and/or the tissue thickness compensator 1140, for example, as described above. For example, the tissue thickness compensator1i150 can be modified to include the apertures 1152 once the tissue thickness comnensator 1150 istransitionedto a glassy state.

[0149] As described above, a tissue thickness compensator such as, for example, the tissue thickness compensator 1150 can be transitioned to a glassy state by beingheatedin an oven (not shown) to atemperature greaterthan or equal to the glass transition temperature of the material composition of the tissue thickness compensator 1150 ut less than the nelntin temperature of the same. A mold 1154 comprising a plurality of posts, dowels, pins, and/or protrusions, for example, such as, for example, needles 1156 can be utilized to create the apertures z152 by inserting the needles 1 156 into the tissue thickness compensator 1150 while the tissue thickness compensator I 150 is in the glassy state. The tissue thickness compensator 1150 can then be allowed to cool to a temperature below the glass transition temperature while the needles 1156 remain inserted into the tissue thickness compensator 1150.In some instances, the needles 1156 can be removed fom the tissue thickness compensator 1150 while the tissue thickness compensator 1150 is in the lassy state. In sore instances, a fan can be used. to generate a flow ofair over the tissue thickness compensator 1150 while the tissue thickness compensator 1150 is engaged with the needles 1156 and/or after the tissue thickness compensator 1150 has been disengaged from the needles 1156. In some instances, a refrigeration process can be utilized to cool the tissue thickness compensator 1150 while the tissue thickness compensator 1150 is engaged with the needles 1156 and'or after the tissue thickness compensator 1150 has been disengaged fom the needles 1156. In various instances, the needles 1156 can be removed after transitioning the tissue thickness compensatory 1150 out of the glassy state. The needles 1156 can remain inserted into the tissue thickness compensator 1150 for a tune period sufficientto permit the tissue thickness compensator1150 to retain, or at least substantially retain, the spaces defining the apertures 1152 whichare occupied by the needles 1156 101501 In certain examples, the needles 1156 can remain inserted for a period oftine from about 30 secondsto about 8 hours, for example, during the time in the glassy state and/or for a period of time from about 30 seconds to about 8 hours, for example, after exiting the glassy state. It at least one example, the needles 1156 can remain inserted for approximately 10 minutes during the time in the glassy state and for approximately 10minutes after exiting the glassy state. Overtime periods for maintaining the needles 1156 inserted into the tissue thicknesscompensator1150

are contemplated by the present disclosure.

[0151] In certain circumstances, the needles 1156 can be removed from the tissue thickness compensatory 1150 prior to transitioning the tissue thickness compensator 1150 out ofthe glassy state. In other circumstances, the needles 1156 can be gradually removed over time. For example, the needles 1156 can be partially removed from the tissue thickness compensator 1150 prior to transitioning the tissue thickiess compensator 1150 out of the glassy state. The needles 1156 can then be filly removed from the tissue thickness compensatory 1150 after transitioning the tissue thickness compensator 1150 out of the glassy state. The reader will appreciate that the greater the depth of insertion of the needles 1156 into the tissue thickness compensator 1150, the greater the depth of the corresponding apertures 1152 that can be created in the tissue thickness compensator i150 101521 Reering again to FIGS. 32-34, in certain instances, the needles 1156 can be heated to a temperature greater than or equal to the m ueltin temperature of thematerial composition of the tissue thickness compensator 1150. In addition, the needles 1156 can be inserted into the tissue thickess compensator 1150to createthe apertures 1152 by melting, or at least partially melting, throughthe regionsof the tissuethicknesscompensator150thatreceivethe needles 1156. In various instances, the needles 1156 can be heated prior to their insertion into the tissue thickness compensatory 1150. In various instances, the needles 1156 can be heated after their insertion into thetissue thickness compensator 1150. In various instances, the needles 1156 can be gradually heated as the needles 1156 are inserted into the tissue thickness compensator 1150. 101531 In certain instances, the needles 1156 may remain positioned within the tissue thickness compensator 1150 for a period oftime sufficient to permit the melted material of the tissue thickness comnpensator 1150 to flow into a desired geometry. Such atime period can range front about 30 seconds to about 8 hours, for example; other time periods are contemplated by the present disclosure. Such a time period can be sufficient to locally affect and/ormelt the material of the tissue thickness cotmpensator 1150 and have it flow into a new geometry. As described herein, such a new geometry can be prescribed by the tooling used to makethe tissue thickness compensator 1150.

[0154] In certain instances, the tissue thickness compensator 1150 canbe allowed to cool, or can be actively cooled, to a temperature below the melting temperature of the tissue thickness compensator 1150 before separating the needles 1156 frot the tissue thickness compensator 1150. In other instances, the tissue thickness compensator I 150 can be allowed to cool, or can be actively cooled, to a temperature below the melting temperature ofthetissue thickness compensator 1150 after separating the needles 1156 from the tissue thickness compensator 1150. 101551 Referring again to FIGS. 32-34, the needles 1156 can be arranged in rows extending longitudinaly along a length of the told 1154 which may correspond to staple rows in a staple cartridge such as, for example, the staple cartridge assembly 20200 (FG 6). For example, as illustrated in FIG. 33, the needles 156 care arranged in six rows which can be configu"red to create six rows of the apertures 1152 that can be configured to receive six rows of the staples 20230 (FIG. 7). In certain circumstances, as illustrated in FIG. 33, the rows of the needles 1156 can be arranged in two groups which are spaced apart and configured to be received in two portions 1158 and 1160 ofthe tissue thickness compensator 1150 thereby creating two groups ofthe apertures 1152 separated by an intermediate portion i162. The intermediate portion 1162 can be positioned, at least partially, over the cartridge knife slot 22015 (FIG. 6), when the tissue thickness compensator 1150 is assembled with staple cartridge assembly 2200 In use, the firing member 10052 (FIG. 10) can be advanced distallyto push the staple legs 20232 (FIG. 8) through the apertures 1152 within the portions 1158 andi 160 and advancethe ttiin portion 10053 (FIG. 10) to transect the interediate portion i162 and separate the portions 1158 and 1160.

[0156] Reterring again to FIGS. 32-34, the apertures 1152 can be configured to extend within the tissue thickness compensator 1150 and terminate at a certain depth within the tissue thickness compensator 1150. The apertures 1152 may comprise uniform depths, as illustrated in FIG. 34. In other circumstances, the apertures 1152 may comprise different depths (not shown). For example, a first row ofthe apertures 1152 may comprise a first depthand a second row of the apertures 1152 may comprise a second depth different fromthe first depth and yet a third row ofthe apertures 1152 may comprise a third depth different from the first depth and the second depth. The depths ofthe apertures 1152 can be determined, at least in part, by the heights of the corresponding needles 1156. For example, a first row of the needles 1156 comprising a first height and a second row ofthe needles 1156 comprising second height greater than first height may create a first row of the apertures 1152 comprising a first depth and a second row ofthe apertures 1152 comprising a second depthwhich isgreater than the first depth. 101571 Referring again to FIGS. 32-34, the needles 1156 can be configured to define a trajectory for the apertures 1152 within the tissue thickness compensatory 1150. In certain circumstances, the needles 1156 can extend alongan axis that is perpendicular and/or substantially perpendicular to a mold surface 1164 of the mold 1154, as illustrated in FIG. 33. Inserting the needles 1156 into thetissue thickness compensator 1150 while maintaining a parallel relationship between the mold surface 1164 and a surface 1166 of the tissue thickness compensator 1150 nia resultin defining a perpendicular and/or substantially perpendicular trajectory for the apertures 1152 relative to the surface 1166 of Ite tissue thickness compensator 150, as ilustraed in FIG. 34. In othercircumstances, Ite needles 1156 can extend from the mold surface 1164 at an oblique angle (not shown) and/or the insertion trajectory ofthe needles 1156 into the tissue thickness compensator 1150 can be at an angle such that the needles 1156 may define a non perpendicular trajectory for the apertures 1152 relative to the surface 1166 of the tissue thickness compensator 1150. In certain circumstances, a grot of the needles 1156 can be parallel and/or substantially parallel to cach other, as illustrated in FIG. 33, resulting in a group ofthe apertures 1152 thatmay be parallel and/or substantially parallel to each other, as illustrated in FIG. 24. In other circumstances, although not illustrated, group ofnon-parallel needles can extend fromthe mold surface 1164 and may result in non-parallel apertures when inserted intothe tissue thickness compensator 1 150. In some circumstances, the needles 1156 can be configured to createapertures within the tissue thickness compensator 1150 that can comprise a partially curved trajectory and/or a partially lineartrajectory. For example, the needles 1156 can extend from the mold surface 1164 in a partially curved trajectory andcan be inserted intothe tissue thickness compensator 1150to create apertures within thetissue thickness compensator 1150 with a corresponding partially curved trajectory.

[0158] Referring again to FIGS. 32-34, some or all of the needles 1156 can comprise blunt distal ends 1168, as illustrated in FIG. 33. In other circumstances, some or all of the needles 1156 can comprise sharp distal ends (not shown). Some or all ofthe needles 1156 can comprise cylindrical, oratleast substantially cylindrical, shapes, for example, as illustrated in FIG. 33. Other shapes are also contemplated by the present disclosure. [0159] In various instances, one ormore oftheneedles 1156 extendingfrom the mold surface 1164 may not be insertable through the full thickness of the tissue thickness compensator 1150. In certain instances, one or more of the needles 1156 extending from the mold surface 1164 cas be insertable through the fill thickness of the tissue thickness compensator 1150 to create openings an/or holes that extend through the full thickness of the tissue thickness compensator 1150. In certain instances, one or more of the needles 1156 extending from the moid surface 1164 can be inserted through a first side of t tissueeethickness compensator 1 50 and exited through a second side of the tissue thickness compensator 1150 which may be opposite the first side, for example. In certain instances, one or more of the needles 1156 may comprise a length greater than the fall thickness of he tissuethickness compensator 1150 to faciltate the insertion of the one or more needles 1156 through the full thickness of the tissue thickness compensator 1150.

[0160] Referring now to FIGS. 35-37, it may be desirable to resize a tissue thickness compensator. For example, one or more dimensions of a tissue thickness compensator may be adjusted to correspond to dimensions of a staple cartrndge in order to provide a better fit to the staple cartridge when the tissue thickness compensator is assembled with the staple cartridge. In certain circumstances, a tissue thickness compensator 1170 can be resized bychanging its height from a first height H1, as illustrated in FIG. 35, to a second height 12, as illustrated in FIG. 36. The tissue thickness compensator 1170 may be similar in many respects to other tissue thickness compensators described herein such as, for example, the tissue thickness compensator 22020 (FIG. 9), the tissue thickness compensator 140 (FIG. 29), and/or the tissue thickness compensator 1150 (FIG. 32). For example, like the compensator 22020, the compensator 1170 can be utilized with the end effector 22090 (FIG. 9) 101611 In various instances, referring again to FIGS. 35-37, the tissue thickness comnpensator 1170 can be prepared using traditional lyophilization techniques and/or any other suitable techniques. In certain instances, the tissue thickness compensator 1170 can be resized, as illustrated in FIG. 37, usitn a thermalpressing process and a mold 1172, for example. The mold 1172 may comprise a receiver 1174 configured to receive the tissue thickness compensator 1170 and anadiustment member 1176 which can be partially insertable into the receiver 1174. The tissue thickness compensator 1170 can be resized when the tissue thickness conpensator 1170 is transitioned into a glassy state. In one embodiment, the tissue thickness compensator 1170 can be heatedin an oven (not shown) to a temperature greater than or equal to a glass transition temperature of the material composition of the tissue thickness compensator 170 but less than the melting temperature of the same. In another embodiment, the receiver 1 174 and/or the adjustment member 1176 may comprise a heating element for transitioning the tissue thickness comnpensator 1170 to the glassy state. The adjustment member 1176 can then be inserted into the receiver 1174 a distance113, for example, as illustrated in FIG. 37, thereby compressing the tissue thickness compensator 1170 and reducing its height from the first height Hi1 to the second height H2. In some instances, the adjustment member t 176 can be inserted into thereceiver 1174 before thetissuethickness comensator 1170 enters into the glassy state oriust as thetissue thickness compensator 1170 enters into the glassy state. The adjustment member 1176 can be held against the tissue thickness compensator 1170 to compress the tissue thickness compensator 1170 for a time period sufficient to perrnit the tissue thickness compensatory 1170 to retain, or at least substantially retain, the second height H2, as illustratedin FIG. 36. The tissuethickness compensatory 1170 can then be allowedto cool to a temperature below the glass transition temperature while under compression from the adjustment member 1176. After transitioning the tissue thickness compensator 1170 out of the glassy state, the adjustment member 1176 can be retracted. in some instances, the adjustment member 1176 can be retracted before the tissue thickness compensator 1170 exits the glassy state. In certain circumstances, the above described resizing process can be utilized to change anotherditmension of the tissue thickness compensator 1170 such as a length or a width of the tissue thickness compensator 1170, for example. In some circumstances, these dimensions can be modified simultaneously or modified sequentially.

[0162] In certain examples, the compression from the adjustment member 1176 can be maintained for a period of time from about 30 seconds to about 8 ours, for example, during the time in the glassy state and/or for a period of time from about 30 seconds to about 8 hours, for example, after exiting the glassy state. In at least one example, the compression from the adjustment member 1176 can be maintained for approximately 10 minutes during the time in the glassy state and for approximately 10 minutes after exiting the glassy state. Other time periods for maintaining the coimpression imposed by the adjustment mieuber 1176 against the tissue thickness compensator 1170 are contemplated by the present disclosure.

[0163] In certain circinustances, the adjustment member 1176 can be used to apply pressure onto the tissue thickness compensator 1170 before the tissue thickness compensator 1170 is transitioned to the glassy state. In certain circumstances, the adjustment member 1176 mayapply pressure to the tissue thickness compensator 1170 while the tissue thickness comnpensator 1170 is heated to reach the glassy state, while the tissue thickness compensator 1170 is in the glassy state, and/orwhile the tissue thickness copensator 1170 is transitioed or cooled to temperature below

the glassy state. In certain circumstances, the pressure applied to the tissue thickness compensator 1170 can be gradually increased toward a threshold as the temperature of the tssue thickness compensator 1170 is gradually transitioned toward the glassy state, for example. In certain circumstances, ie pressure applied to the tissue thickness compensator 1170 can be removed, gradually removed, or at least partially reduced as the tissue thickness compensator 1170 exits the glassy state, before the tissue thickness compensator 1170 exits the glassy state, and/or afterthe tissue thickness conpensator 1170 exits the glassy state.

[0164] The reader will appreciate that the different moldsutilized in the modificationprocesses described above such as, for example, the molds 1144, 1154, and/or 1172 are illustrative examples. Other mold designs and contgurations can also be employed to manipulate tissue thickness compensators i a variety ofways. Furthermore, the forces involved in manipulating a tissue thickness compensator need not only be compressiveforces. For example, tensileforcescan alsolbeutilized to mtodity, rspe,and/orresize a tissue thickness coensator insminlarnianners tothosedescribedabove. Forexamplethe tissue thickness compensator 1170 can be stretched usingtensile forcesto reduce its height fron the first height Hi (FIG. 35) to the second height H2 (FIG. 36), for example, using a modification process that is similar in many respects to the modification processes described above. In certain circunstaices, combinations of tensile and compressive forces can be used tomanipulate a tissue thickness compensator during a modification process.

[0165] Reterring again to FIGS. 35-37, it may be desirable to modify the porosity of a tissue thickness compensator for use in a surgical procedure. A tissue thickness compensator may comprise a porous, open cell foam ad/or a porous, closed cell foam, for example. Traditional lyophilization techniques may provide some control over a tissue thickness compensator's porosity but such control may not be easily reproducible aid may need additional fine adjustments that may not be obtainable by traditional lyophilization techniques. As illustrated in FIGS. 35-37, the height of the tissue thickness compensator 1170 can be changed firon the first height II (FIG 35) to the second height H2 (FIG. 36), for example, using the modification process described above. In addition, porosity of the tissue thickness compensator 1170 can also be modified using the same and/or a similar modification process. For example, the tissue thickness compensator 1170 may comprise a first porosity (FIG. 35) prior to the modification process and a second porosity (FIG. 36) after completion of the modification process, as described above. The change in porosity can be attributed, at least in part,to the compressive forces and/or the energy applied to the tissue thickness compensator 1170 by the adjustment member 1176 during the modification process described above.

[0166] Further to the above, the tissue thickness compensator 1170 may comprise a plurality ofpores 1180. Some or all of the pores 1180 may be altered in position, size, and/or shape, for example, as a esult of the modification process described above, For example, one or more of the pores 1180 may comprise a spherical, or substantially spherical, shape priortothe modification process which maybe alteredto anoval, or substantially oval, shape as result ofthe modification process. In at least one example, one or moreof the pores 1180 may corise atfistsize priortothe modification process and a second size different from the first size as a result of the modification process. In certain circumstances, as described below in greater detail, the porosity changes can be localized to one or more regions or zones of the tissue thickness compensator 1170.

[0167] Furthermore,incertaincircumstances,thechangeinporosityof the tissue thickness compensator 1170may be accompanied by a changein density of the tissue thickness compensator 1170. In other words, as the adjustment member1176 is advanced against the tissue thickness compensator 1170, compressive forces may reduce space occupied by the tissue thickness compensatory 1'70 thereby causing aterial andior pore redistribution which may yield an increase in the density ofthe tissue thickness compensator 1170 and/or a reduction in its porosity. In certain circumstances, as described below in greater detail, the density changes can be localized to one ormore regions or zones of the tissue thickness compensator 1170.

[0168] Further1tothe above,tie change in potosiy aid/or density of the tissue thickness compensator 1170 may yield a change in the springrate of the tissue thickness compensator 1170. A tissue thickness compensator's spring rate can influence itsaityto compensate for tissue thickesswhen the tissue thickness compensator is deployed against tissue captured by staples such as, for example, the staples 20230 (FIG. 8), as described above in greater detail, Furthernore, a tissue thickness compensator's spring rate can also ifuece its ability to apply pressure against tissue captured with the tissue thickness compensator by a staple. In other words, a change in a tissue thickness conpensator's spring rate may change the pressure exerted by the tissue thickness compensator against tissue captured by a staple. Since different tissetypes may respond more positively to certain pressures, fine control over a tissue thickness compensatory's spring rate can be advantageous. 101691 As iltstrated in FIGS. 35-37, the tissue thickness compensator 1170 may comprise a first spring rate (FIG. ) which may be altered or modified to a second spring rate (FIG. 36) different from the first spring rate using the modification process described above. For example, as described above, the adjustment member 1176 can be advanced against the tissue thickness compensator 1170 while the tissue thickness compensator 1170 is in the glassy state. in response, the tissuethickness compensatory 1170 may be compressed which may cause a change inthe spring rate ofthe tissue thickness compensator 1170. The adjustient member 1176 can be retained in the advanced position for a period of time sufficient to permit the tissue thickness compensator 1170 to retain, or at least substantially retain, the change in spring rate. In addition, the tissue thickness compensator 1170 can be allowed to cool below the glass transition temperature of its material composition while maintaining the pressure applied by the adjustmentmember 1176 against the tissue thickness1comensator170.

[0170] In certain instances, theadjustment member1176can bemaintainedin the advaiecedpositionagainst the tissue thickness compensator 1170 for a period of time from about 30 seconds to about 8 hours, for example, during the time in the glassy state and/or for a period of time from about 30 seconds to about 8 hours, for example, after exiting the glassy state. In atleast one example, the adjustmentmember 1176 can bemaintained in the advanced position against the tissue thickness compensator 1170 for approximately 10 minutes during the time in the lassy state and forapproximately 10 minutes after exiting the glassy state. Other time periods formaintaining the adjustment member 1176 in the advanced position against the tissue thickness compensator 1170 are contemplated by the present disclosure. 101711 In certain circumstances, the adjustment member 1176 can be used to apply pressure onto the tissue thickness compensator 1170 to change the spring rate of the tissue thickness compensator 1170 before thetissue thickness compensator 1170 is transitioned to theglassy state. In certain circumstances, the adjustment member 1176 may apply pressure to the tissue thickness compensator 1170 while the tissue thickness compensator 1170 is heated to reach the glassy state while the tissue thickness compensator 1170 is in the glassy state, and/or while the tissue thickness compensator 1170 is transitioned or cooled to a temperature below the glassy state. In certain circumstances, the pressure applied to the tissue thickness compensator 1170 can be gradually increased toward a threshold as the temperature of the tissue thickness compensator 1170 is gradually increased to transition the tissue thickness compensator 1170 toward. the gassy state, for example. In certain circumstances, the pressure applied to thetissue thicknesscomnpensator1170canberemoved,graduallyremoved, or at least partially reduced as the tissue thickness compensator 1170 exits the glassy state, before the tissue thickness compensator 1170 exits the glassy state, and/or after the tissue thickness compensatory 1170 exits the glassy state.

[0172] Referring again to FIGS. 35-40, the tissue thickness conmpensator 1170 may be manufactured with a native spring rate using traditional lyophilization techniques and/or any other suitable techniques. As described above, the spring rate of the tissue thickness compensator 1170 can influence its ability to apply pressure against tissue captured with the tissue thickness compensator 1170 by a staple. The modification process described above may be utilized to adjust the native spring rale of the tissue thickness compensator 1170 to adjust its ability to apply pressure against tissue captured with tie tissue thickness compensator 1170 by the staple. In certain circumstances, the native srine rate o the tissue thickness compensator 1170 can be increased froma first spring rateat point A (FIG, 40) to a second spring rate including and up to a maximum spring rate at point B (FIG. 40). In certain circumstances, such increase of the spring rate ofthe tissue thickness compensator 1170 can be achieved by applying compression forces to the tissue thickness compensator 1170 using the adjustment member 1176 while the tissue thickness compensator 1170 is in the glassy state, as explain in the modification process described above. As illustrated in FIG. 40, the point B represents a maximum elastic yield of the tissue thickness compensatory 1170. As such, any additional compression applied by the adjustment member 1176 to the tissue thickness compensatory 1170 beyond a threshold compression at the point B may produce a decrease in the spring rate of the modified tissue thicness compensator 1170.Forexample,as illustrated in FIG. 40, the spring rate at the point C lower than the spring rate at the point B even though the compression force applied by the adjustment member 1176 to the tissue thickness compensator 1170at point C is greater than the compression lorce applied at the point

.

[0173] As discussed above, one or more processes can be used to affect the spring rate, and/or any other property, of a material used in conjunction with a fastener cartridge ad/or a surgical fastening instrument, for example. Thespring rate, and/or any other property, ofthe material may change throughout the modification process or processes. Such a change imayte gradual in some circumstances, while in other circumstances, the change may be sudden. In vanous instances, one ormoreofthe steps ofthemodification process may cause an increase in the spring rate of the material while one or more steps may cause a decrease in the spring rate of the material. Ultimately, the net change inthe spring rate can be measured as a comparison between an original spring rate before the modification process begins and a subsequent spring rate after the modification process has been completed. In various instances, a material may comprise an altered spring rate after the material has been heated id then cooled.

[0174] Incertaincircumstances,itmaybedesirabletoapplyoneormoreoftheabovedescribedmodification processes to a tissue thiciess compensator. For example, a first modification process can be utilized to modify porosity ofthe tissue thickness compensator, as described above withrespect to the tissue thicnesscompensator 1170. A second modification process, following the first modification process, can be utilized to alter a surface ofthe tissue thickness compensator, as described above with respect to the tissue thickness compensator 1140. Furthernore, a third modification process can be utilized to nodify the tissuethickness compensator to include a longitudinal slot similar to the longitudinal slot 1122 of the tissue thickness compensator 1120. in yet a fourth modification process, the tissue thickness conensator carbe mnodied to include aNertures similar to the apertures 1152 o" the tissue thickness comnensator 1150. The reader will appreciate that some of above mentioned modifications can be combined or grouped in a single modicatiot process. For example, a mold can be designed to iiclude the needles 156 of the moid 1154 and the central beam 1128 ofthe mold 1126. Other modification arrangements are contemplatedby the present disclosure.

[0175] Referring now to FIGS. 38 and 39, a tissue thickness compensator such as, for example,tissue thickness compensator 1 t90 can be altered or modified usig one or more of the modification processes described above to include portions with different spring rates, porosities, and/or densities. In certain circumstances, the tissue thickness compensator 1190 can be modified using one or more of the modification processes described above to include a gradient pore morphology (i.e. small pores gradually increasing in size to large pores across the thickness of the tissue thickness compensator 1190 in one direction). Suchmorphology couldle more optimal for tissue in-growth or hemostatic behavior. Further, the gradient could also be compositional with a varying bio-absorption profile. A short term absorption profile may be preferred to address hemostasis while a long term absorption profile may address better tissuehealing without leakages.

[0176] Referring again to FIGS. 38 and 39, the tissue thickness compensator 1190 may include one or more zone geometries that are different from the remainder of the tissue thickness compensator i;96. For example, as illustrated in FIG. 38, the tissue thickness compensator 1190 may include one ormore protmding portions such as,for example, protrudin portion 1196. In addition, the tissue thickness comupensator 1190 may comprise a uniform, or at least a substantially uniform, first spring rate, first porosity, and/or first density through the tissue thickness compensator

1190 including the one or more zone geometries, as illustrated in FIG. 38. In certain circumstances, the tissue thickness compensator 1190 can be altered or modified using one or more of themodification processes described above to alter or modify the one or more zone geometries and/or to induce localized changes in the first spring rate, the first porosity, and/or the first density, for example. The modified tissue thickness compensator 1190 may comprise one or more modified zones with different spring rates, porosities, and/or densities from other modified zones and/or thefirstspring rate,thefirstporosity ador the first density, respectively,oftheremainderofthetissuethickness compensator 1190. In certain circumstances, the resulting one or more modified zones may correspond to the one or more zone geometries. For example, as illustrated in FIG. 39, thetissuethickness compensator 1190 may be altered or modified to level, orat least substantially level, the protruding portion 1196 and to form a flat, or at least a substantially flat, surface 1198, for example. The modified tissue thickness compensator 1190 may include a first portion 1192 comprising the first spring rate, the first porosity, and/or the first density and a second portion 1194 comprising a second spring rate, a second porosity, and/or a second density, which can be different from the first spring rate, the first porosity, and/or the first density, respectively. The second portion 1194 may correspond to the protrndu portion 1196 and can result from the leveling, or at least substantially leveling, ofthe protruding portion 1196 to for thie flat, or at least substantially flat, surface 1198, for example. In certain respects, the geometry ofthe protruding portion 1196 prior to the modification ofthe tissue thickness compensator 1190 mirrors, matches, or resembles the geometry of the second portion 1194 after the tissue thickness compensator 1190 has been modified.

[0177] Referring again to FIGS. 37-39, the tissue thickness compensatory 1190 can be altered or modified using the mold 1172, in asimilarrianner to thetissue thickness compensator 1170 Forexample, e tissue thickness compensator 1190 can be heated in the receiver 1174to a temperaturegreaterthanorequalto aglasstransition temperatureofthe material compositionofthe tissue thickness compensator 1190butless than the melting temperature of the same. In certaincircumstances, the adjustmentmember 1176 can be advanced againstthe protruding portion 1196, while the tissue thickness compensator 1190 is in the glassy state, thereby compressing the protruding portion 1196 andrearranging its geometry to form the second portion 1194, as illustrated in FIG. 39. Further to the above, the adjustment member 1176 can be configured tomaintain compression against the protruding portion 1196 for a time period sufficient to permit the tissue thickness compensator 1190 to retain, or at least substantially retain, the modification imposed by the adjustment member 1176. Thetissue tickness compensatory 1190 can be allowed to cool or can be actively cooled to a temperature below its glass transition temperature while under compression from the adjustment member 1176. Aftertransitioning the tissue thickness compensatory 1190 out ofthe glassy state, the adjustment member 1190 can be retracted. Thetissue thickness compensator 1190mayretain, or at least substantially retain, the second portion 1194, as illustrated in FIG. 39. In certain circumstances, the adjustmentmenmber 76ay apply pressure onto the protrumdingportion1196whilethetissueticknesscompesator 1190 is heated to reach the glassy state, while the tIssue thickness compensator 1190isinthe gassy state, and/or whilethetissuemihickiessomensator1190 is transitionedorcooled to atemperature below the glassy state.In certaincircumstancetbepiessureapplied to theprotruding portion 1196 of the tissue thicknesscompensator 1190 can be gradually increased toward a threshold as ie tenmerature of the tissue thickness compensator 190 is gradually increased to transition the tissue thickness compensator 1190 toward the glassy state, for example. In certain circumstances, the pressure applied to the protruding portion 1196 of the tissue thickness compensator 1190 can be renmovedigraduallyremoved,oratleastpartiallyreduced asthe tissuetlicness compensator 1190exits theglassy state, before the tissue thickness compensator 1190 exits the glassy state, and/or after the tissue thickness compensator 1190 exits the glassy state.

[0178] Referring now to FIGS. 41-43, a tissue thickness compensator such as, for example, tissue thickness compensator 1200 can be prepared using traditional lyophilization techniques and/or any other suitable techniques. In addition, the tissue thickness compensator 1200 can be modified or altered foruse in a surgical procedure, for example. The tissue thickness compensator 1200 can be similarin many respects to othertissue thickness compensators such as, for example, the tissue thicness compensator 22020 (FIG. 9) and/or the tissuethickness compensator 1 120 (FIG. 26). For example, like the issuC thickness compensator 22020, the tissue thickness compensator 1200 can be utilized with the end effector 22090. Furthermore, as illustrated in FIGS. 41-43, the tissue thickness compensator 1200 can be modified to include a lonnitudinal slot 1202 which, like theknife slot 22025, may define a tissue thickness compensator knife path for the cutting portion 10053 between a first stapling portion 1204a and a second stapling portion 1204b. Furthermore, the first stapling portion 1204a and the second stapling portion 1204b can be similar in many respects to the first stapling portion 22021a (FIG.9) and the second taping portion 22021b (FIG. 9) ofthe tissue thickness compensator 2 20 20. In addition, the slot 1202 can be confiired to releasably connect the first stapling portion 1204a and the second stapling portion 1204b such that, in use with the end efiector 22090,thecuttinportion 10053 can be advanced distally through the slot 1202 to transect the slot 1202 and separate the first stapling portion 1204a and thesecond staplin g portion 1204b.

[0179] Referring again to FIGS. 41-43, the tissue thickness compensatory 1200 can be modified prior to assembly with an end eftector such as, for example, the end effector 22090 (FIG.9). Alteratively, thetissue thickness compensator 1200 can be modified after it has heen assembled with an end effector. As described above, the tissue thickness compensator 1200 can be prepared using traditional Iyophilization techniques and/or any other suitable techniques. A space creator 1206 can be utilized to modify te tissue thicness compensator 1200 in a thermal pressing process, as illustrated in FIGS. 41-43. For example, the space creator 1206 can be heated toatemperature greater than or equal to a meting temperature ofthe material composition ofthe tissue thickness compensator 1200. The space creator 1206 cai then be aligned with and insertedinto the tissue thickness compensator 1200 to form the longitudinal slot 1202. The space creator 1206 may melt through thetissue thickness compensator 1200 to create space for the longitudinal slot 1202. The space creator 1206 can be retracted upon reaching a desired depth within the tissue thickness compensator 1200. In certain circumstances, the thermal pressing process can be repeatedby reinserting the heated space creator 1206 through the tissue thickness compensator 1200 to widen the space created for the iongitudina' slot 1202.

[0180] Referring again to FIGS. 41-43, the space creator 1206 may comprise ahot wire. For example, the space creator ;206 may comprise a thin, tart metal wire, which can be made of nichrome or stainless steel, for example, or a thicker wire Preformed into a desired shape. The hot wire can be heated viaelectrical resistance to a desired temperature. As the hot wire of the space creator 1206 is passedthrough thematerial of the tissue thickness compensator 1200, the heat from the hot wire may vaporize the material Just in advance of contact. In certain circumstances, the hot wire may comprisea cylindrical, or substantially cylindrical, shape, as illustrated in FIG. 42. The depth of the longitudinal slot 1202 can depend, in part, onthe insertion depth of the space creator 1206 through the tissue thickness comnpensator 1200 and the width ofthe longitudinal slot 1202 can depend, in part, on the diameter of the hot wire of the space creator 1206.

[0181] In certain instances, the space creator 1206 can be partially inserted through the full thickness of the tissue thickness compensator. In certain instances, the space creator 1206 cai be completely inserted through the full thickness ofthe tissue thickness compensator 1200 to create openings, holes, and/or slots extending through the full thickness of the tissue thickness compensator 1200. In certain instances, the space creator 1206 may be inserted through a first side ofthe tissue thickness compensator 1200 and exited through a second side ofthe tissue thickness compensator 1200 which may be opposite the first side, for example. 101821 Many processes are disclosed herein which utilize thermal energy to modify a tissue thickness compensator. Such processes can be referred to as felting processes. In certain instances, a felting process may also utilize the application of compressive and/or tensile forces to a tissue thickness compensator. In other instances, a felting process may not utilize the application of compressive and/or tensile forces to a tissue thickness comnpensator, In either event, the felting processes disclosed herein can also be utilized to modify and suitable implantable layer and/or buttress material, for example.

[0183] Invarious circumstances, the tissue thickness compensator assembly may comprise a polymeric composition. Thepolymeric composition may comprise one or more synthetic polymer and/or one ormore non synthetic polymer. The synthetic polymer na comprise a synthetic absorbable polymer and/or a synthetic non absorbable polymer. In various circumstances, tie polymeric composition may comprise a biocompatible foam, for example The biocoinpatibe foam may comprise a porous, open cell foam and/or a porous, closed cell foam, for example. The biocompatible foam can have a uniform pore morphology or may have a gradient poremorphology (i.e. small pores gradually increasingin size to large pores across the thickness of the foam in one direction). In various circumstances, the polymeric composition maycomprise one or more of a porous scaffold, a porous matrix, agel matrix, a hydrogel matrix, a solution matrix, a filamentous matrix, a tubularmatrix, a composite matrix, a membranous matrix, a biostable polymer, and a biodegradable polymer, and combinations thereof For example, the tissue thickness compensatory asserbtly rimay comprise a foan reinforced by a filamentous matrix or may comprise a foam having an additional hydrogel layer that expands in the presence of bodily fluids to further provide the compression oti the tissue, In various circumstances, a tissuethickness compensator assembly could also be comprised of a coating on a material an&/or a second or third layer that expands in the presence of bodily fluids to further provide the cotmpression on the tissue. Such layer could be ahydrogel that couldbe a synthetic and/or naturally derived material and could be eitherbiodurabeand/orbiodegradabie,forexample Incertaincircumstances a tissue thickness compensator assembly could be reinforced with fibrous non-woven materials or fibrous mesh type elements, for example, that canprovide additional flexibility, stiffness, and/or strength. In various circumstances, a tissue thickness compensator assembly thatlhas a porous morphology which exhibits a gradient structure such as, for example, small pores on one surfaceand larger pores on the other surface. Such morphology could be more optimal for tissue in-growthor hemostatic behavior. Further, the gradientcouldbe also compositional with avaryingmio absorptionprofile. A short term absorption profile may be preferred to address hemostasis while a long term absorption profile may address better tissue healing without leakages.

[0184] Examples of non-synthetic polymers include, but are notlimited to, lyophilized polysaccharide, glycoprotein, elastin, proteoglycan, gelatin, collagen, and oxidized regenerated cellulose ()RC). Examniples of synthetic absorbable polymers include, but are not limited to, poly(lactic acid) (PLA),poly(L-lactic acid) (PLLA), polycaprolactone (PC), polyglycolic acid (PGA), poly(trimethylene carbonate) (TMC), polyethylene terephthalate (PET), polyhydroxyalkanoate (PA), a copolymer of glycolide and c-caprolactone (PGCL), a copolymer of glycolide and trimethylene carbonate, noly(glycerol sebacate) (PGS), polydioxanone, poly(orthoesters), polyanhydrides, polysaccharides, poly(ester-amides), tyrosine-based polyarylates, tyrosine-based polyiminocarbonates, tyrosine-based polycarbonates, poly(D,L-iactide-urethane), poy(B-hydroxybutyrate),poly(E-caprolactone), polyethyleneglycol (PEG), poly[bis(carboxylatophenoxy) phosphazene], poly(amino acids), pseudo-poly(amino acids), absorbable

polyurethaies, and combinations thereof. In various circumstances, the polymeric composition may comprise from approximately 50%to approximately 90% by weight of the polymeri composition of PLLA and approximately% to approximately 10% by weight of the polymeric composition of PC., for example, In at least one embodiment, the polymeric composition may comprise approximately 70% by weight of PLLAand approximately 30% by weight of PCL, for example. In various circumstances, the polymeric composition may comprise from approximately 55% to approximately 85%lby weigtlnof thepolmeric composition ofPGA and 15%0 o 45% by weightofthe polymeric composition ofPCL, for example. In at least one embodiment, the polymeric composition may comprise approximately 65%by weight of PGA and approximately 35% by weight or PCL, for example. in various circumstances, the polymeric composition may comprise from approximately 90% to approximately 95% by weight of the polymeric composition of PGAand approximately 5% toapproximately 10% by weight of the polymeric composition of PLA, for example.

[0185] In various circumstances, the synthetic absorbable polymermay comprise a )ioabsorbable, biocompatible elastomeric copoivmer. Suitable bioabsorbable, biocompatible elastomeric copolymers include but are not limited to copolymers ofesilon-caprolactoneandglycolide (preferably having a mole ratio ofepsilon-caprolactone togtycolide offrom about 30:70 to about 70:30, preferably 35:65 to about 65:35, and more preferably 45:55 to35:65); elastomeric copolymers of epsilon-caprolactone and lactide, including L-.actide, D-lactide blends thereofor lactic acid copolymers (preferably having a mole ratio of epsilon-caprolactoneto lactide of from about 35:65 to about 65:35 and more preferably 45:55 to 30:70) elastomeric co-olymers ofp-dioxaone (,4-dioxan-2-one) and lactide incLdin- L lactide, D-lactide and lactic acid (preferably having a mole ratio ofp-dioxanone to lactide of from about 40:60 to about 60:40); elastomeric copolymers of epsilon-caproactone and p-dioxanone (preferably having a mole ratio of epsilon-caprolactone to p-dioxanone of from about 30:70to about 70:30); elastoeric copolymers ofp-dioxanone and trimethylene carbonate (preferably having a mole ratio of p-dioxanone to trimethylene carbonate offroi about 30:70 to about 70:30); elastomeric copolymers of trimethty'lee carbonateand glycolide (preferably having amole ratio or trimethylene carbonate to glycolide of from about 30:70 to about 70:30); elastomeric copolyier oftrimethylene carbonateand lactide including L-iactide, D-iactide, blends thereof or lactic acid copolytmers (preferably having a mote ratio of trimethylene carbonate to lactide of from about 30:70 to about 70:30) and blends thereof. In one embodiment, the elastomeric copolymer is a copolymer of glycolide and epsilon-caprolactone. In another embodimnlent, the elastomeric copolymer is a copolymer of lactide and epsilon-caprolactone

[0186] The disclosures of U.S. Patent No. 5,468,253, entitled ELASTOMERIC MEDICAL DEVICE, which issued onNovember21, 1995, and U.S Paent No. 6,325,810,entuiledFOAMI BUTTRESS FOR STAPLING APPARATUS, which issued on December 4, 2001, arehereby incorporated by reference in their respective entireties.

[0187] Invarious cimstansth synthetcabsorbabpolymernmaycompriseoneormoreof90/10 poly(glycolide-L-lactide) copolymer, commercially available from Ethicon, Inc. underthe trade designation VICRYL (polyglactic 910), polyglycolide, commercially available from American Cyanamid Co. under the trade designation DEXON, polydioxanone, commercially available from Ethicon, Inc. under the trade designation PDS, poly(glycoide trinethylene carbonate) random block copolymer, commercially available froth Ameaticvanarnid Co. nrder the trade designation MAXON, 75/25 poly(glycoide-E-aprolactone-poligecaprolactoe 25) copolymer, commercially available from Ethicon under the trade designation MONOCRYL, for example.

[0188] Examples of synthetic non-absorbable polymers include, but are not limited to, foamed polyurethane, polypropylene(PP),polyethylene (PE, po)ycarbonate, olamnides, such as nylon, polyviniychloride (PVC), polymethylmetacrylate (PMMA), polystyrene (PS), polyester, polvethereferketone (PEEK), polytetrafluoroethylene (PTFE),polytritluorochloroethylene(PTFCE), polyvinyifluoride(PVF),fluorinated ethylenepropylene(FEP), polyacetal, polysulfone, and combinations thereof The synthetic non-absorbable polymers may include, but are not limited to, foamed elastomers and porous elastomers, such as, for example, silicone, polyisoprene, andrubber. In various circumstances, the synthetic polymers may comprise expanded polytetrafluoroethylene (ePTFE), commerciallyavailable fromW. L. Gore & Associates, Inc. under the trade designation GORE-TEX Soft Tissue Patch and co-polvetherester urethane foam commercially available from Polyganicsunder the trade designation NASOPORE.

[0189] The polymeric composition ofatissue thickness compensator assembly iaybe characterizedby percent porosity, pore size, and/or hardness, for example. In variotis circumstances, the polymeric composition may have a percent porosity from approximately 30% by volume to approximately 99% by volume, for example. In certain circtImstances, the polymeric composition may have a percent porosity from approximately 60% by volume to approximately 98% by volume, for example. In various circumstances, the polymeric composition may have a percent porosty from approximately 85% by volume to approximately 97% by volume, or example. In at least one emtodiment, the polymeric composition may comprise approximately 70% by weight of PLLA and approximately % by weight of'PCL, for example, and can comprise approximately 90 porosity by voltime, for example. In at least one such embodiment, as a result, the polymeric composition would comprise approximately 10% copolymer by

volume, In at least one embodiment, the polymeric composition may comprise approximately 65% by weight of PGA and approximately 35% by weight of PCL, for example, and can have a percent porosity from approximately 93% by volume to approximately 95% by volume, for example. In various circumstances, the polymeric composition may comprise a greater than 85% porositylby volume. The polymeric composition may have a pore size from approxunately5micrometerstoapptoxtcimately20icronmeters, forexample. In various circumstances, the polymeric composition may have a pore size between approximately 10 micrometers to approximately 100 micrometers, for example. In at least one such embodiment, the polymeric composition can comprise a copolymer of PGA and PCL, for example In certain circumstances, the polymeric composition may have a pore size between approximately 100 micrometers to approximately 1000 mcrometers, for example. In atleast one such embodiment, the polyneric composition can comprise a copolvmer of PLLA and PCL, for example. According to certain aspects, the hardness of a polymeric compositionmay be expressed i terms of the Shore Hardness., which can defined as the resistance to permanet indentation of a material as determined with a duromer, such as a Shore Durometer, In order to assess the durometer value for agiven material, a pressure is applied to the material with a durometer inrenter foot in accordance with ASTM procedure D2240-00, entitled, "Standard Test Method for Rubber Property-Durometer Hardess", the entirety ofwhichis incorporated herein by reference. The durometerindenter foot may be applied to the material for a sufficient period of time, such as 15 seconds, for example, wherein a reading is then taken from the appropriate scale. Depending on the type of scale being used, a reading of0 can be obtained when the indenter foot completely penetrates the material, and a read-i of t00 can be obtainedwhen no penetration into the material occurs, This reading is dimensionless. In various circumstances, the durometer may be determined in accordance with any suitable scale, such as Type A and/or Type00 scales, for example, in accordance with ASTM D2240-00. In variis circumstances, the polymeric composition of atissue thickess compensator assembly may have a Shore A hardness value from approximately 4 A to approximatelyI 16 A, for example, vhich is approximately 45 00 to approximately 00 on the Shore 0O ran e. in at least one such embodiment, the polymeric composition can comprise a PLLA/PCL copolyner or a PGA/PCL copolymer, for example. in vanous circumstances, the polymeric composition of a tissue thickness compensatorassembly may have a Shore A Hardness value of less than 15 A. In various circumstances, the polymeric composition of a tissue thickness compensator assembly may have a Sore A Hardness value of less thi 10 A. in various circumstances, thepolymeric composition of a tissue thickness compensator assembly may have a Shore A Hardness value ofless than 5 A. in certain circumstances, the polymeric material may have a Shore 00 composition value from approximately 35 00 to approximately 75 00, for example.

[0190] In various circumstances, the polymeric composition may have at least two of the above-identifmed properties. In various circumstances, the polymeric composition imay have at least three of the above-identified properties. The polymeric composition may have a porosity from 85% to 97% by volume, a pore size from 5 ticrometers to 2000 micrometers, and a Shore Alhardness value from4 A to 16 A and Shore 0 hardness value from 00 to 65 O, for example. In at least one embodiment, the polymeric composition may comprise 70% by weight of the polymeric composition of PLAand 30% by weight of the polymeric composition of PCL having a porosity of % by volume, a pore size from 100 micrometers to 1000 micrometers, anda Shore Ahardness value from 4 A to16 A and Shore 00hardness value from 45 OO to 65 00, for example. in at least oneembodiment, the polymeric composition may comprise 65% by weight ofthe polymeric composition ofPGA and 35%lbyweight of the polymeric composition of PCL having a porosity from 93% to 95%by volume, a pore size from 10 micrometers to 100 micrometers, and a Shore A hardness value fro 4 A to 16 A and Shore OO hardnessvaluefrom 45OO)to6500.for example.

[0191] Invariouscircumstances,thepoiymericcompositionrmaycompriseapharmaceuticallyactiveagent.The polymeric compositionmayrelease a therapeutically effective amount of the pharmaceutically active agent. In various circumstances, the pharmaceutically active agent maybereleased as the polymeric composition is desorbed/absorbed. In various circumstances, the oharmaceutically activeageit may be released into fuid, such as, for example, blood, passing over or through the polymeric composition. Examples of pharmaceutically active agents may Inlude, but re notlimited to, hemostatic agents and drugs, such as, for example, fibrin, thrombin, and oxidized regenerated cellulose (ORC); anti-inflammatory drugs, such as, for example, diclofenac, aspirin, naproxen, sulindac, andhydrocortisone; antibiotic and antimicrobial drug or agents, such as, for example, triclosan, ionic silver, ampicillin, gentamicin, polymyxin B, chloramphenicol; and anticancer agents, such as, for example, cisplatin, mitomnycin, adriaycin.

[0192] Various methods are disclosed herein for altering a tissue thickness compensator. Such methods could be used to alter any suitable layer for use with a fastenercartridge and/or a surgical fastening instrument, forexamle. Such a laver can comprise aless than one hundred percent dense composition which can be created utilizing any suitable process. For instance, such processes can include, for example, extrUding, injection molding, weaving,

lyophilization, gas-foaming, and/or melt-blowing processes. Some processes may produce a foam while other processes may not produce a foam; however, in any event, all such embodiments are contemplated for Use with all of the embodiments disclosed herein.

[0193] Invariousembodmens,referringtoFIGS.44-46,anendeffectorofasurgicalfasteninginstrument,suchas end effect 100, for example, can be configured to capture, fasten, ad/or incise tissue, The end effector 100 can include a fastener cartridge 110 and, in addition, a firing member 140 which can be advanced through the fastener cariridge 110 to deploy staples removably stored within the staple cartridge 110 into tissue captured within the end effector 100. In various instances, the firingmember 140 can be advanced from a proximal position (FIG. 44) toward a distal end of the end effector 100 to simultaneously deploy the staplesand transect the tissue, There are some circumstances, however, where it may notrbe desirable to advance thefiring neniber 140 toward the distal end ofthe end etfector 100. For instance, the fastener cartridge 110 ofthe end effector 100 can be removable and/or replaceable and, in the event that a fastener cartridge110is not positioned within the end effector 100, it may not be desirable for the firing member 140 to be advanced within the end effector 100. In the event that the firing member i40 were to be advanced through the end effector 100 without a fastener cartridge positioned within the end effector 100, a kif'e edge 142 ofthe firing member 140 mayincise tissue captured within the end effector 100without simultaneously fastening the tissue. Simiarly, in the event that the fastener cartridge positioned within the end effector 100 has been previously used, or expended, andat least some ofthefasteners have been deployed frorn the fastener cartridge, it may not be desirable for the firing member 140 to be advanced within the end effector 100. In the event that thefiring member 140 were to be advanced through the end effector 100 with a previously expended fastener cartridgepositioned within the end effector 100, theknife edge 142 of thefiring member 140 may incise tissue captured within the end effector without simultaneously fastening the tissue. In various embodiments, the end effector 100 can include one or more lockoutsystems which can prevent the firing member 140from beingadvanced. distally when a fastener cartridge is not present within the end effector 100 and/or when the fastener cartridge positioned within the end effector 100 has been at least partially expended. Various lockout systems are disclosed in US, Patent No. 6,988,649, entitled SURGICAL STAPLING INSTRUMENT HAVING A SPENT CARTRIDGE LOCKOUT, and issued on January 24,

2006. The entire disclosure ofU.S. PatentNo.6,988,649entitled SURGICALSTAPLINGINSTRUMENT HAVING A SPENTCARTRIDGE LOCKOUT, is incorporated by reference herein.

[0194] Referring again to FIGS. 44-46, the fastener cartridge 110 can include cartridge body and a tissue thickness comupensator 120 wherein, fluther to the above, the tissue tickness compensator 120 can beimplanted against issue captured by the end effector 100 by fasteners removably stored within the cartridge body. Thetissue thickness compensator 120 can be positioned above a top surface, or deck, of the cartridge body wherein staples 180 removably stored within staple cavities defined in the cartridgebody can be ejected from the staple cavities by a firin member, such as sled 130dandor firingmember 140, for example. In certain embodinents, the fastenercartridge 110 can fItherinclude drivers configured to support the staples 180 and transmit the movement of the sled 10 to the staples 180 in order to move the staples 180 between an unfired position and a tired position. In various instances, the staples 180 can be at least partially enibedded in the tissue thickness compensator 120 when the staples 180 arein their unfired positions and, in certain instances, the staples 180 cat hold the tissue thickness conptensator 120 in position over the caitridge deck when the staples 180 are in their unfired position. In the event that thetissue thickness compensator 120 were to be noved relative to the cartridge body and/or the staples 180 prior to deploying the staples 180 into tissue, in some instances, the tissue thickness compensator 120 may move the staples 180 relative to or away from their preferred positions. Moreover, in the event that the tissue thickness compensator 120 were to be removed from the cartridge 110 prior to te staples 180 being deployed, the cartridge 110 may no longerlbe suitable for its originally intendeduse. In view of the foregoing, as discussed it greater detail below, the end effector 100may include a lockout configured to prevent thefiring member 140 and/or the sled 130 fro being advanced distally to deploy the staples 180 in the event that the tissue thickness compensator 120 is removed from, or becomes at least partially islodged frot, the cartridge body prior to dhe staples 180 being deployed.

[0195] Referring again to FIGS. 44-46, the tissue thickness compensatory 120 can comprise, one, a body 121 conigured to be capturediby the staples 180 and, two, a lockout pin 122 extending from the body 121. In various instances, the lockout pin 122 caninclude a first end 123 embedded in the body 121 and a second end 124 positioned intermediate the firing meu.er 140 and the sled 130 when the tissue thickness compensator 120 has not beenemoved from or substantially moved from a suitable position over the cartridge body deck. In such a position, the second end 124 of'the lockout pin 122 canbe positioned intemediate a shoulder, or shelf, 134 defined on the sled 130 and a

protrusion 144 extending distally fromthe firing bar 140. Stated another way, when the lockout pin 22 is positioned intermedate the sled 130 and the firmbar 140, the lockout pin 122 and the sled 130 cart co-opeate to support the firing bar 140 in an unlocked position above a lockout shoulder 112defined in the fastener cartride ".10such that, when a distal firing force is applied to the firing bar 140, the firing bar 140 can advance the sled 130 distalvy to fire the staples 180. Wlen the tissue thickness compensator 120 is removed from te cartridge 110 and/or sufficiently dislodged from a desirable position relative to the cartridgelbody, referring primarily to FIG. 45, the lockout pin 122 tay no longer be positioned intermediate the sled 130 and the firing netber 140 and/or tay otherwiselbe unable to support the firing member 140 in its unlocked position (FIG. 44). In such circumstances, the firing enber 140may become positioned. ina locked position sucthtat te distal advanceent of the firing member 140 is prevented byte lockout shoulder 112. In at least one such circumstance, the end effector 100 canfurther include a biasingmember, suchasaspring,forexample, configured to bias the firing member 140 into its locked condition. In certain circumstances, the biasinmember can bias the firing member 140 into contact with the sled 130, for instance, without the lockout pin 122 positioned therebetween which can comprise the locked position ofthe firingmember 140,

[0196] As a result of the above, the cartridge 110maybecome inoperable if the tissue thickness compensator 120 is prematureyremoved from the cartridge 110 1 In circumstances, the lockout pin 22 maycompriseausewhich deactivates the cartridge 110 in the event that thetissue thickness compensator 120is removed before the firing member 140 is advanced distally. In various circumstances, the lockout pin 122may comprise a keywhichmaiainins the cartridge 110 in an unlocked condition when the key is positioned between the sled 130 and the firing member 140 and permits the cartridge 110 to enter into a locked condition in the event that the tissue thickness compensator 120 is removed from the cartridge 110 before the firing member 140 is advanced distally, i.e., before the firing meniber 140 begins its firing stroke. When the firing member 140 is in its locked-ont condition and cannot be advanced distally, the knife edge 142 of the firin member 140 is unable to incise the tissue captured within theend effector 100. Moreover, in such circumstances, the firing member 140 cannot advance the sled 130 distally to irethe staples180. Thus, the tissuethickness compensatorlockout can preventthe tissue captured within the end effector 100from being incised and stapled when the tissue thickness compensator 120 is not positioned on, or properly positioned on, the cartridge 110. In the event thathe Firing member 140 is advanced distally bee the tissuetiickness conpensator 120 is removed, or dislodged, the firing member 140 can complete the firing stroke, or at least a portion ofthe firing stroke, oftheend effector 100. Insuch instances, the sled 130 is advanced distallyso thatoneor more ranps 132 defined on the sled 130 can lift-the staples 180 and that aknife edge 142 ofthe ringmember 140 canincisethe tissue thickness compensator 120 ad/orthe tissue captured withinthe end effec'or 100, In some circumstances, the firing member 140 can contact the lockout pin 122 and displace it out of the way as the firingmember 140 is advanced distally. In such circumstances, the lockout pin 122 can be flexible. In various instances, the lockout pin 122 can be comprised of a bioabsorbable material and/or a biocompatible material, for exaniple. In certain circumstances, the firingnmemer 140 can incise the lockout pin 122 as the Firing member 140 is advanced distally. In any event, the purpose of the lockout pin 122 may become obsolete once the firing member 140 has been at least partially advanced. Stated another way, the tissue thickness compensator lockout can serve as an initial check to verify that a tissue thickness compensator is present within the end effMctor and, once that initial check has been made, the firing stroke of the end effector can proceed. 101971 Referring again to FIGS. 47-50, an end effector 200 can comprise an anvil 260 and, in addition, a fastener cartridge 210 including a cartridge body 214 and a tissue thickness compensator 220 wherein, ihrther to tie above, the tissue thickness compensatory 220 can be implanted against tissue captured by the end effector 200 by fasteners removably stored within the cartridge body 214. Thetissue thickness compensator220canbepositionedabove atop surface, or (lek, 211 of the cartridgebody 214 wherein staples removably stored within staple cavities defined il the cartridge body 214 can be ejected from the staple cavities by a firing member, such as a sled 230 and/or a firing member 240, for example. In certain embodiments, the fastener cartridge 210 ca further include drivers configured to support the staples and transmit the movement ofthe sled 230 to te staples in order to move the staples between an unfired-position and afiredposition. In various instances, the staples canbeat least partial embedded in the tissue thickness corpensator220 when the staples are in their unfired positions and, in certain instances, the staples can hold the tissue thickness comnpesator 220 in position when the staples are in their unfired position. In the event that the tissue thickness cotuNesator220 were to be moved relative to the cartridgebody 214 and/or the staples prior to deploying the staples into the tissue, in some instances, the tissue thickness compensator 220 may move the staples relative to or away from their preferred positions. Moreover, in the event that the tissue thickness compensator 220 were to be removed from the cartridge 210 prior to the staples being deployed, the cartridge 210may no longer be suitable for its originally intended use. In view of the foregoing, as discussed in greaterdetail below, the end effector 200 may include a lockout conngured to prevent the firing member 240 and/orthe sled 230 from heirg advanced distally to deploy the staples in the event that the tissue thickness compensator 220 is removed from, or becomes at least partially dislodged fro, the cartridge body 214 prior to the staples being deployed.

[0198] Referring again to FIGS. 44-46, the tissue thickness compensatory 220 cart coprise, ote, a body 221 conngured to be captured by the staples and, two, aioop, or tether, 222 extending front tie body 221. Invarious stances, referring primarily to FIG. 47, the loop 222 can cot praise ends which are at least partially embedded in the body 221 and an intermediate portion extending between the ends which can be releasably engaged with the sled 230. In certain instances, the loon 222 can comprise a suture or flexible thread, for example. In som nstanc, the ioop 222 can be comprised of a bioabsorbablematerial and/or a biocompaotible material, for example. Referring primarily to FIG. 48, the sled 230 can include a longitudinal body portion 236, a hook 238 extending from the body portion 236, and a slot 237 defined between the body portion 236 and the hook'238. As illustrated in FIG. 48, the loop 222 is positioned within the slot 237 whenthe tissue thickness compensator 220 is positioned over thecartridge deck 211 andthe sed 0ad thefitingmember240areinannunired position. As also illustrated in FIG. 48, a distal projection 244 extending from the firing member 240 is positioned against and/or above a support shoulder 234 defined on the sled 230 whichlholds the firing member 240 in an unlocked position, i'e. in a position in which the distal movement of the firing member 240 will not beimpeded, orat least substantiallyimpueded, by a lockout shoulder 212 denied n the end effector 200 wheti a firin notion is applied to the firing member 240. Thus, whei the sled 230 holds the firing member 240 in its unlocked position, referringto FIG. 49, the firing member 240 will slide past the lockout shoulder 212 to advance the sled 230 distally, fire the staples removably stored within the cartridge body 214, and incise the tissue thickness compensator and the tissue positioned within the end effector 200 with a knife edge 242. As illustrated in FIG. 49, the loop 222 can slide out of the slot 237 defined iii the sled 230 when the sled 230 is advanced distally.

[0199] In the event that the tissue thickness compensator 220 is removed from the artridge210orsubstantially moved from a suitable position over the deck 211 of the cartridge 210, referring now to FIG. 50, the tissue thickness compensator 220 can pull the sled 230 distally such that the firing member 240 is no longer supported by the sled 230. More particularly, theloop222 ofthe tissue thickness comtpeiisator220 positioned within te slot237 canpull the sled 230 distally from its unfired position such that the support shoulder 234 is no longer positioned under the distal projection 244 of the firing member 240. in such circumstances, the firing member '240tray shift downwardly iito a locked position wherein the distal movement of the firing member 240can be impeded by the lockout shoulder 212.

In certain circumstances, the end effector 200 can further include a biasing member, such as a spring, forexample, which can bias the firing member 240 into its locked conditio. When the firing member 240is in its locked condition, the firing member 240 cannot be moved distally to advance the sled 230, fire the staples from the cartridge body 210, and/or incise the tissue captured within the end effector 200 Although the sled 230 may be advanced distally when the tissue thickness compensator 220 is removed from the cartridge 210, the sled 230, in various cirtcunstances, may not be advanced sUfficiet todeploy the staples from the cartridge 210. When the user ofthe surgical instrument recognizes that the firing member 240 is in a locked-out condition, the user can removethe staple carindge 210 from the eud effector 200 and replace itwit a staple cartridge 210,forexample, in which thetissue thickness compensator 220 is correctly positioned over the deck 211 and the sled 230 has not been advanced distally fromiits unfired position.Otherembodimentsdar contempatedinwhichastalecartridgeisnotremovablefromthe end effctor; in such embodiments, the end effector may be entirely replaced inthe event thatthe tissue thickness conpensator is removed from the staple cartridge and/or the firing member enters into a locked-out condition.

[0200] Turning now to FIGS. 51-53, a staple cartridge 310 can include a cartridge body 314 and a sled 330 movably positioned within the cartridge body 314. Simlarto the above, the cartridge body 314 can include a piirly of fastener cavities, such as fastener cavities 3'6, for example, and a longitudinal slot, such as knifislot 318, for example, defined therein. The sled 330 can include a central body portion 336 slidably positioned within the knife slot 318 and aiook 338 extending froni the central body portion 336. Referring primarily to FIG. 51, a tissue thickness compensator 320 of the cartridge 310 can include a body portion 321 and a catch 322 extending from the body portion 3' wherein the catch 322 can be releasably retained in a slot 337 defined between the hook 338 and the central body portion 336 when the sled 330 is in itsunfired,or unadvanced, position. Similar to the above, the catch 322 can include eis 323 noted wiftin the body 321 and can extend proxinially from the body 321 of the tissue thickness compensator 320 wherein, in the event that the tissue thickness compensator 320 is removed from the cartridge body 314, for instance, the catch 322 can pull the sled 330 distally such that a support shoulder 334 defined in the central body portion 336 is no longer able to support a firing member, such as firing member 240, for example, thereon and such that the tiring member may enter a locked out state. In various instances, a user ofthe surgical instrument may attempt to reassemble or reposition the tissuethickness compensator 320 over the deck 311 of the cartridge body 314; however, the firing member 340 will still remain in a locked out condition as the repositioning of the tissue thickness compensator 320 will not reset the sled 330. Thus, such an arrangement can prevent the cartridge 310 from being used if it has been previously tampered with. 102011 In various instances, referring again to FIGS. 51-53, at least a portion of the hook 338 extending from the central portion 336 ofthe sled 330 and/or the slot 337 defined therebetween can extend above the deck 311. In certain instances, at least a portion.ofthe hook 338 extending from te central portion 336 of the sled 330 and/or the slot 337 defined there'btween can extend above the knife slot 318. In such embodiments, the catch 322 can be easily slid into the slot 337 when the isu tickness compeiisator 320 is assembled to tlecartridge body34 In certaiinstances, the catch 322 can be positioned above or against the deck surface 311 of the cartridge body 314. In various instances, referring primarily to FIG. 53, te cartridge body 314 can include a recess or pocket 319 definedtherein within which the hook 338 can be positioned when the sled 330 is in its unfired, or unadvanced, position. In such an embodimet, the top ofthehook 338 may be positioned below the deck surface 311. In various instances, the pocket 319can further include one or more ramped surfaces 313 which are defied in the distal end ofthe pocket 319and extend downwardly from the deck surface 311. In some instances, the catch 322 can abut the ramped surfaces 313 when the sled 330 is advanced distaly and, in such circumstances, the hook 338 can then separatefrom the catch 322. In various instances,the recess 319 can be configured to facilitate the assembly of the catch 322 to the sled 330when the tissue thickness compensator 320 is assembled to the cartridge body 314. In various embodiments, the slot 337 can extend longitudinaly and can include a closed distal endan open proxinal end wherein the catch 322 can be slid into the slot337 from the open proximal end, In the event that the tissue thickness compensator 320 is not premnaturely removed ordisodged from the cartridge 314, the sled 330 can be advanced dismally such that the catch 322 exits the slot 337 through the distal end thereof and suchthat ramps 332 defined on the sled 330 can eject the staples from the staple cartridge 310.

[0202] In various instances, a tissue thickness compensatorcan be adhered to a sled utilizing at least one adhesive. In such instances,the adhesive attachment between the tissue thickness compensator and the sled can be strong enough to permit the tissue thickness compensator to pull the sled distally in the event that the tissue thickness compensator is removed from the cartridge. When the sled is advanced distally by the firing member as part of the firing stroke, the adhesive attachment between the tissue thickness compensator and the sled may fail thereby permitting the sled to slidedistally relativetothe tissuethickness compensator.Invarisinstances,atssue thickness compensator can bebonded to a sized utilizing aheat steak process and/or athermoform process. In such instances, thebond. between the tissue thickness conmeusator and the sled can be strong enough to permit the tissue thickness compensator to pull the sled distally in the event that the tissuethickness compensator is removed from the cartridge. When the sled is advanced distally by the lringmember as part of thefring stroke, the bond between the tissue thickness compensatory and the sled may fail thereby permitting the sled to slide distally relative to the tissue thickness compensator.

[0203] In sometistances, a loop, a catch, and/or tag, for example, can be integrally formed with a tissue thilckiess cotupensator. In various instances, the loop, catcp, and/or tag, for example, can comprise a unitary piece ofmaterial with the tissue thickness compensator. In some instances, an additional layer can be attached tothetissue thickness compensatory. This layer, it various instances, cancomprise a mounting portion engaged with the sled.

[0204] Turning nowto FIG. 54, a sled 430 can include, similar to the above, a central body portion 436 and, in addition, a plurality of ramps 432 which are configured to eject staples removably stored within a cartridge body, for example. Also similar to the above, the body portion 436 can include a hook 438 extending therefrom wherein a slot 437 can be defined between the body portion 436 and the hook 438. In certain instances., the slot 437 can include a closed distal end 437a and an open proximal end 437d. In various instances, the slot 437 can furtherinclude a first portion 437b extending in a first direction and a second portion 437c extending in a second direction. In certain instances, the First portion 437b can extend along a longitudinal axis and the second. portion 437c can extend along a

second axis which is transverse to the longitudinal axis. In at least one such instance, the second portion 437c can extend at an angle relative to the First portion 437b.

[0205] Turning now to FIGS. 55-58, a sled assembly 530 can include a first portion 535 and, in addition, a second portion 536 which is movable relative to the first portion 535 between an unlocked position (FIGS. 55 and 57) arid a locked position (FIGS. 56 and 58). The first portion 535 can include, one, a central portionconfigured to slide within a longitudinal slot, such as a knife slot518 defined in a staple cartridge 510, forinstance, and, two, a plurality of ramps532configuredtoeject staplesremovably storedwithin the cartridge 510. The central portion of the first portion 535 can include a first slot 533aand a second slot 533b defined therein. The first slot 533aand the second slot 533b can be configured to receive pins 531a and 531b, respectively, extending from the second portion 536. The first

pin 531acan be configured to slide within the first slot 533a and the second pin 5311) can e configured to slide within the second slot 533b in order to permit the second portion 536to rotate relative to the first portion 535. In various instances, the first pin 53Ia can be closely received within the first slot 533a such that the first slot 533a can constrain the motion ofthe first pin 53la along a first path and, similarly, the second pin 53lb can be closely received within the second slot 533b such that the second slot 533b can constrain themotion ofthe second pin 531b along a second path. Referring primarily to FIG. 57, the second portion 536 olfthe sled assembly 530 can comprise an arm configured to slide within the knife slot 5t8 wherein the arm can include a support shoulder 534 defined on the proximal end thereof and ahook538 defined on the distal end thereof Simiar to the above, the support shoulder 534 canbeconfigured to support a firing nernber 240, for example, in an unlocked position when the sled assembly 530 is in a proximal, unfired position and the tissue thickness compensator 220, forinstance, is positioned over and/or againstthe deck surface 511 of the cartridge 510. Also similar to the above, the hook 538 can be configured to releasably hold the loop222 ofthe tissue Itickness compensator 220 such that, in the event that the tissue thickness compensator 220 were to be removed fromand/or substantially displaced relative to the cairtidge body, the loop 222 could pull on the second portion 536 to pivot the second portion 536 into its locked position as ilustrated in FIGt 58. In such a locked position of the second portion 536,thesupport shoulder 534 may no longer support the distal

projection 244 of the f mrmember ing 240 and the firing member 240 can drop downwardly into its locked position. As depictedin FIG. 58, the rotation ofthe second portion 536 intoits locked position can move the support shoulder 534 distallv and/or downwardlyaway fromthe firing member 240. As also depicted in FIG. 58, the firing member240 can include alock 541 extending from opposite sides thereof which can be configured to abut thelockout shoulder 212 when the firing member 240 is in its locked position. When the firing member 240 is held in its unlocked position by the sled assembly 530, the locks 541 may not contact thelockout shoulder 212 and the firing member 240 can be advanced through the cartridge 510. 102061 In various instances, as discussed above, a portion of a staple-driving sled mayextendabove the deck surface of a cartridge body. For instance, referring againto FIGS. 52 and 54, the hook 338 of the sled 330 (FIG. 52) and/or the hook 438 of the sled 430, for example, can extend above the deck surface. In such instances, the hook 338 and/or the hook 438 can translate distally above the deck surface and, in some instances, contact the tissue thickness comensatorpositionedagainst or above the deck surface. In certain instances, thehook 338 and/or thehook 438 can lift the tissue thickness compensator upwardly away from the cartridge body and facilitate the progressive release of the tissue thickness compensatory from the cartridge, For instance, the hook 338 and/or the hook 438 can beginat the proximal end of the tissue thicknless compensator and move toward the distal end ofthe tissue thickness compensator in order to initially lift the proximal end ofthe tissue thickness compensator and then progressively liftitawayfrom the cartridge deck until the distal end of tle tissue tickness compensator is eventually lifted away from the cartridge body. In other instances, as discussed in greater detail further below. it may be preferable for the portion of the sled contacting the tissue ttickness conipensator to deflect downwardly and/orotherwise not disturb the tissue sickness compensator as the sled is advanced distally.

[0207] Turning now to FIGS. 59 and 60, a staple cartridge 610 can include a cartridge body 614, a tissue thickness compensator 620 releasably retained to the cartridge body 614, and a sled 630 configured tolongitudinally traverse the cartridge body 614 and eject staples removably stored therein. The sled 630 can include main body portion 635 having aplurality of ramp surfaces defined thereon, a support shoulder 634, and an arm 636 extending from the body portion 635. In various instances, the arm 636 can beassembled to the main body portion 635. For instance, the arm 636 can include a first end embedded in the main body portion 635 and a second end including a hook 638, for example. In various instances,the arm 636 can comprise a cantilever beam extending from the main body portion 635. In certain instances, the ann 636 can be comprised of a resilient and/or flexible material, for example. Similarto the above, a slot 637 can be defined between the hook 638 and the arm 636 which can be configured to releasably hold a portion of thetissue thickness compensator 620 when the sled 630 is in its proximal, unfired position. In the event that the tissue thickness compensator 620 is pulled off of the cartridge body 614, for example, the tissue thickness compensatory 620 can pull the sled 630 distallyaway from a ling member so thatthe firingniember enters into a locked out condition.

[02081 In various ins tances, further tothe above, at least a portion ofthearm 636, such as the hook 638, for example, can extend above the deck surface 611 of the cartridge body 614. In certain instances, the arm 636 can be engaged with aloop, for example, extending from the tissue thickness compensator 620 when the sled 630 is in its proximal position (FIG. 59) and, as the sled 630 is advanced distally, the ar 636 can disengage fon the loop. As the sled 630 is advanced distally, in certain instances, the arm 636 cart contact the body portion 621 ofthe tissue thickness compensator 620 and flex downwardly. In various instances, tie deflected arm 636 can slide within a lorgitudinal knife slot 618 defined in the cartridge body 614 as the sled 630 is advanced dismally. In some instances, referring to FIG. 60, the distal end of the longudinal slot 618 can be defined by a nose wall, or roof, 619 wherein, wher the sled 630 reaches adistal end 617of the cartridge 610i, thearm 636 can slide under the nose wall 619 such that the i-ring stroke ofthe end effector can be completed. In some instances, the arn 636 may not be deflected, or substantially deflected, downwardly by the tissue thickness compensator620 wherein, when thearm 636 reaches the end of the longitudinal slot 618, the arm 636 can contact the-nose wat 618 and flex downwardly in order to slide thereunder as illustrated in FIG. 60. In various circumstances, as a result, the flexible arm 636 can permit the firing stroke to be completed and for the sled 630 to be parked at the distal end ofthe cartridge.

[0209] Turning now to FIG. 61, a sled, such assled assembly 730, for example, can include a main body portion 735 and a movable arm 736. Similar to the above, the main body portion 735 can include one orniore staple-driving ramps 732 and a support shoulder 734 configured to support a firing member in an unlocked position, as described above, The am 736 can include afirst end pivotablyand/or rotatably totnted to the main body portion 735 and a second end including a hook 738 configured to bereasably engaged with a tissue thickness compensator, as described above. When the sledassembly 730 isadvanced distally, the hook 738 can detach from the tissue thickness compensator; however, the upper surface of thelhook'738 can remain in contact with le bottom surface of-the tissue thickness compensator. Insuch circumstances, the arm 736 can pivot downwardly into tieknifeslot 318, for example, in order to slide inder the tissue thickness compensator. More particularly, the arm736canivotfroma raised,or uppermost, position (FIG. 61)to lowered, or depressed,position. In various instances, the sled assembly 730 can further include a resilient biasing member, such as a spring 731, for example, configured to bias the aru736 into its raised position. When the arm 736 has been rotated downwardly into its lowered position, the spring 731 can apply a biasing force to thearm 736 which is transmitted into the tissue thickness compensator. In certain instances, the spring 731 can be positionedintermediate the arm 736 and a frame portion 733 defined on the main body portion 735. In variousinstances, the spring731 can comprise a cantilever spring or leaf spring, for example, extending from the arm 736. When the arm 736 is pushed downwardly, the cantilever spring can be confieured to flex and/or slide along the frane portion 731, for instance. In variousembodiments, the main body portion 735 can farther include a stop shoulder 73), for example, which can limitthe upward rotation, ortravel, of the arm 736. In any event, similarto the above, the arm 36 can be conFigured to rotate downwardly when it contacts the roof 6l19and permit the firing stroke to be completed.

[0210] In various instances, a staple can comprise a base and one or more legs extending from the base. In certain instances, a staple car comprise a base includinga first endand a second end, a first leg extendingfrom the first end, and a second leg extending from the second end. In some instances, the staple can be formedfrom a continuous wire which comprises thefirst leg, the base, and the second leg A first end of-thecontinuous wire can comprise a tip of the first staple leg and a second end of the continuous wire can comprise a tip ofthe second staple leg. One such staple, i.e., staple 800, is depicted. in FIG. 62, for example. The staple 800 can include a base 802, a first stapleeg 804 extending from a first end of the base 802, and a second staple leg 804 extending from a second end of thebase 802. The first staple leg 804 can include a first tip 806 and, similarly, the second staple leg 804 can include a second tip806. In various instances, the tips 806 can be configured to penetrate tissue, such as tissue T depicted in FIG. 62 for example. In some instances, the tips 806 can be sharp and can be formed by a coining process, for example. In various embodiments, the wire can be comprised of titanium and/or stainless steel, for example.

[0211] Invarious embodiments,thestaple800can be I-shaped, or at least substantially U-shaped,forexample, when it ismits untorned configuration. In such embodiments, the legs 804 of the staple 800 can be parallel, or at .east substantially parallel, to one another Moreover, in such embodiments, the legs 804 can be perpendicular, or at teastsubstantially perpendicular, to the base 802. In certain embodiments, the staple 800 can be V-shaped, or atleast substantially V-shaped, for example, when itis in its unformed configuration. In such embodiments, the legs 804 of the staple 800 are not parallel to one another; rather, thelees 804 ca extend i non-parallel directions. Moreover, in such embodiments, one or both of the legs 804 are not perpendicular to the base 802 whereir one or both of the legs 804 can extend in directions which are oblique othe base 802, In various instances, the legs 804 may extend, or splay, outwardly with respect to a center or nidline of the staple. In any event, the staple 800 can be removably stored within a staple cartridge, ejected from the staple cartridge to penetrate tissue, as illustrated i FIG. 62, and then contact an anvil positioned on the opposite side of the tissue. The anvil can be configured to deform the staple 800 into any suitable shape, such as a B-form configuration, for example, as also illustrated in FIG. 62. Various formedstapie configurationssuch as the B-form cotfiguration, orexample,candefineatissueentrapmentarea,suchas tissue entrapment area 807, for example, configured to entrap tissue within the staple.

[0212] As discussedabove,astaplecan beremovablystored within a cavity defied in a cartridgebody. A cartridge body 810 is depicted in FIG. 63 which can include one ormore staple cavities 812 defined therein. Referring to FIGS, 63, 68, and 69, each staple cavity 812 can include a first end 814 and a second end 814. Incertain embodiments, such as embodiments including a longitudinal end effector, forexample, the first end 814 can comprise a proximal end of the staple cavity 812 and the second end 814 can comprise a distal end of the staple cavity 812. In various instances, a staple can be positioned within a staple cavity 812 such that a first leg 804 ofthe staple 800 is positioned in the first end 814 of the staple cavity 812 and a second leg 804 is positioned in the second end 814. In various instances, a staple cavitywidthcanbe defined between the ends 814 of a staple cavity 812. Thebase802 ofa staple can be defined bya base width which can be equal to or shorter than the staple cavity width, for example. In certain instances, a staple can comprise a staple width which can be defined between the tips 806 of the staple legs 804. In some embodiments, the staple width can be equal to the staple cavity width. In various enbodiments, the staple width can be wider than the staple cavitywidth. In such embodiments, the legs 804 car be in contact with the ends 814 ofa staple cavity 812 and can be resilientlybiasedinwardly by the ends 814 when the staple is positioned within the staple cavity 812. Whenthe staple is iiRed upwardly out of the staple cavity 812, the legs 804 can resiliently splay outwardly as they emerge from the staple cavity 812. For example, the staple can be positioned within the staple cavity 812 such that the tips 806 ofthe stale es 804 do not extend above a top surface, or deck, of the cartridge body 810 when the staple is in its unfired, or unlifted, position. In such a position, the tips 806 can be positioned. flush witl or recessed below the deck 811 of the cartridge body 810. Altematively, the tips 806 of the legs 804 can at least partially extend above the deck 811 of the cartridge body 810. In any event, as the staple is lifted tipwardly, the staple tips 806 can emerge above the deck 8 t1 and splay outwardly as the legs 804 emerge from the cavity 812. At some point during the lifting ofthe staple, the legs 804 may no longerbe in contact with the ends 814 of the staple cavity 812 and the legs 804 may no longer be biased inwardly by the sidewalls ofthe staple cavity 812. 102131 In various instances, an anvil can include one or more pockets configured to receive the tips 806 of the staple legs 804 as the staple 800 is ejected from the staple cartridge. The anvil pockets can be configured to turn, or bend, the staple legs 804 inwardlytoward one another, for example. In other instances, the anvil pockets can be configured to turn, or bend, the staple legs 804 outwardly away from one another, for example. In some instances, however, one or more ofthe staple legs of a staple niay iss a staple pocket andmay not be properly deformed. In certain instances, one or more ofthe staple legs may not contact the anvil and may not be deformed at all. In either event, the staple may not properly capture and/or retain the tissue within its tissue entrapment area. Moreover, themisformed or unformed staple may not be able to apply a desired compressive pressure to the tissue. In some instances, the tisformed founfrmed staple may rot be retained in the tissueand can become dislodged from the tissue.

[0214] Referringagainto FIG. 62,thestaple 800, andorvariousotherstaplesdisclosedherein, canincludeoneor more barbs extending therefrotn Itvariousmstancesebarbscanbeconfiguredtoenaetissuecapuredwithin and/orsurounding the staple. In certain instances, the barbs can assist in retaining the staple within thetissue, especialy when the staple has been misformed or unformed. The staple 800 can include barbs extending from one or both of the lees 804. For instance, each leg 804 can include one or more barbs 808 which fiaceoutwardly from the center of the staple 800 and/or one ormore barbs 809 which face inwardly toward the center of the staple 800, for example. In certain instances, the barbs 808 can extend away fromt the tissue entrapment area 807 and/or thebarbs 809 can extend toward or into the tissue entrapment area 807. As depicted in FIG. 62, both of the staple leos 804 of staple 800 can include barbs 808 and barbs 809. In some instances, the staple legs 804 can include barbs 808, bntnot barbs 809. A staple 820 is depicted in FIG. 63 which includes barbs 808, but not barbs 809. In some instances, the staple legs 804can includebarbs 809, but notbarbs 808. Staples 830, 840, 850, 860, and 870 are depicted inFIGS. 64, 65, 66, 67, and 68, respectively, which include barbs 809, but not barbs 808. In some embodiments, a first leg 804 of a staple can nclude'arbs 808 while a second leg 804 ofthe staple can include barbs 809, for example. 102151 In various instances, the legs 804 and the base 802 of a staple can define a staple la.ne when the staple is in an unfornedconfiguration. The barbs 808 can extend otwardly from the legs 804 within such a staple plane, Similarly, the barbs 809 can extend inwardly from the legs 804 within such a plane. In sone instances, a staple can include barbs which extend laterally with respect to sucha staple plane. Otherembodiments are eivisioned in which the legs 804 and the base 802 do not lie within, or entirely lie within a single plane. In such embodiments, the barbs can extend in any suitable direction. In various embodiments, referring now to FIG. 67, a stapic, such as staple 860, for example, can include barbs 803 extending from the base 802, In various instances, thebarbs 803 can extend inwardly toward the tissue entrapment area 807 of the staple 860. Incertain instances, the barbs 803 can extend outwardly away from the tissue entrapment area 807. As ilustrated in FIG. 67, thebarbs 803 can extend within a staple plane defined by the legs 804 and the base 802. In certain instances, thebarbs 803 can extend laterally with respect to such a staple plane. Various exemplary barb configurations are discussed in greater detailfurther below.

[0216] In various instances, a staple leg 804 can comprise an array of barbs 808 which extends along the entire lengthdter. In somre instances, a staple leg 804 cancomprise an array of barbs 808 which extends along less than the entire length thiereof By way of example, referring to FIG. 62, the legs 804 ofthe staple 800 each comprise an arrayof barbs 808 which extends along less than the entire length of the legs 804. Similarly, referringto FIG 63, the legs 804 ofthe staple 820 each comprise an array of barbs 808 which extends along less than the entire length ofthe legs804. With regardto the staple 800, for example, anarrayofbarbs 808 can extend along each of the legs 804 fron the base 802 of the staple 800 toward the tips 806 of the legs 804. As illustrated in FIG. 62, the arrays ofbarbs 808 may not extend to the tips 806 of the legs 804. In various instances, the arrays of barbs 808 can extend along half, or approximately half, the lengths ofthe legs 804, for example; however, any suitable length ofthe barb arrays coLd be utilized. For instance, the arrays of barbs 808 can extend along less than half or more than half of the lengths of the legs 804. In some etboditnents, an array of barbs 808 can extend .along each of the legs 804 from the tips 806 of the

legs 804 toward the base 802. In such embodiments, the array of bars 808 may not extend to the base 802. In some embodiments, a leg 804 can cotprise an array of barbs 808 which (oes notextend to the tip 806 of the leg 804 or the base 802. In certain embodiments, a leg 804can comprise more than one array of barbs 808.

[0217] In various instances, urther to the above, a staple leg 804 can comprise anarray of barbs 809which extends along the entire length thereof. By way of example, referring to FIG. 64, the legs 804 of the staple 830 each comprise an array of barbs 809 which extends along the entire length ofthe legs 804. In some instances, a staple leg 804 can comprise an arrayofbarbs 809whichextends along less than the entire length thereof. By way ofexample, referring to FIG. 65, the legs 804 of the staple 840 each comprise an array of barbs 809which extends along less than the entire length of the legs 804. Similarly, referring to FIG, 68, the legs 804 of the staple 870 each comprise an array of barbs 809 which extends along less than the entire length ofthe legs 804. Wni regard to the staple 840, for example, an array of barks 809 can extend along each of the legs 804 from the base 802 ofthie staple 840 toward the tips 806 ofthe legs 804. As illustrated in FIG. 65, the arrays ofbarbs 809 may not extend to thetips 806 ofthe legs 804. In various instances,thearrays ofbs809canextendalong half,orippoxinatelyhalfthelengthsofthelegs804,for example; however, any suitable length ofthe barb arrays cond be utilized. For instance, the arrays of baibs 809 can extendalong less thanhlfor more than half of the lengths ofthe legs 804. In some embodiments, an array of barbs 809 can extend along each ofthe legs 804 fromthe tips 806 of the legs 804 toward the base 802. In such embodiments, the array of barbs 809 may not extend to the base 802. In some embodiments, as illustrated in FIG. 66, a leg 804 can comprise an array of barbs 809 which does not extend to the tip 806 of the leg 804 or the base 802. In certain embodiments, a leg 804 can comprise more tha one arrayofbarbs 809. 102181 Various barb configurations are depicted in FIGS. 70-73, although any suitable barb configuration couki be utilized. Referring to FIG. 70, a staple leg 804 can include at least onebarb 809, for example. In varios instances, the barb 809 can comprise a prong. The prong can include f[ist surface 809a'and a second surface 809b which can extend from the perimeter 805 ofthe staple leo 804. The first surface 809a can comprise an inclined surface, a convex surface, and/or aconcave surface, for example. The second surfce 809b can comprise a flat, or an at least substantially flat, surface, for example. In various instances, the first surface 809a andthe second surface 809b can converge at an edge 809c, for example. The barb 809 can be forced utilizing any suitable process. For instance, the barb 809 can be formed utilizing a stamping process. In at least oneembodiment, a forming die, for example, can be utilized to strike the perimeter 805 of the wire comprising the leg 804 in order tounset, or disturb,enoughmaterial to create the barb 809. In various instances, a barb can comprise any suitable nib or spur, for example. In various embodiments, thebarb 809 can be tapered. In various instances, thelbarb 809 can include a base adjacentto the perimeter 805which is thicker than a tip of the barb 809.

[0219] Refertrg now to FIGS 68, 69,71, and 71A, a staple leg 804 can include at least one barb 879, foiexample. In at least one embodiment, the barb 879 can extend around a portion of the perimeter 805 of the stapeleg 804. In various instances, thebarb879 can include a first surface 879a and a second surface 879b which can extend froi the perimeter 805 of the staple lee80. The first surface 879a can comprise an inclined surface, a convex surface, and/or a concave surface, for example. The second surface 879 can comprise a flat, or an at least substantiallyflat, surface, for example. In various instances, the first surface 879a and the second surface 879b can converge at an edge 879c, for example. In various instances, the edge 879c can be arcuate, for example. The barb 879c an be formed utilizing anysuitable process. Forinstance, the barb 879 can be formed utilizina staying procesIn atleast one embodnient, a forming die, forexample, can be utilized to strike the perimeter 805 of the wire comprising the leg 804 in order to upseo, or disturb, enough material to create the barb 879. Referring primarily to FIG. 7A, the wire comprising the leg 804 can be defined by a diameter 801 and the barb 879 can be defined by a diameter which is larger than the diameter 801. Correspondingly, the wire comprising the leg 804 can be defined by a radius and the barb 879 can be defined by a radius which is larger tanr the wire radius. InHvarious erbodiments, the barb 879 can be tapered. In various instances, the barb 879 can include a base adjacent to the perimeter 805 which is thicker than a tip of the barb 879.

[0220] Reterring now to FIG. 72, a staple leg 804 can include at least onebarb 889, for example. In at least one embodiment, the barb 889 can extend around the entiretyof the perimeter 805 of the staple leg 804. Invarious instances,the barb 889 caninclude a first surface 889a and a second surface 889b which can extend from the

perimeter 805 of the staple leg 804. The first surface 889a can comprise aninclined surface, a convex surface, and/or a concave surface, for example. The second surface 889b can comprise a flat, or an at least substantially flat, surface, for example. In various instances, the first surface 889aand the second surface 889 can converge at an edge 889c, for example. In various instances, the edge 889c can be arcuate, for example. The barb 889 can be firmed utilizing any suitable process. For instance, the barb 889 can be formed utilizing a stamping process. In at least one embodirent, a forming die, for example, can be utilized to strikethe perimeter 805 of the wire comprising the leg 804 in order to upset, or disturb, enough material to create the barb 889. The wire comprising the leg 804 can be defined by a wire diameter and the barb 889 can be defined bydiameter whichis larger thanthe wire diameter. Correspondingly, the wire comprising the leg 804 can be defined by a radius and the barb 889 can be defined by a radius which is 1ager than thewire radius Itvarious embodiments, the barb 889 can be tapered. In various instances, the barb 889 can include a base adjacent totie perimeter 805 which is thicker than a tip of the barb 889.

[0221] Refering now to FIG 73, a staple leg 804 can include at least one barb 899, for example. In various instances, the bar 899 can comprise a prong. The prong can include a first surface 899a and a second surface 899b wvhichca extend fromthe perimeterof thestaple leg804. Thefirst surface899a cacomprise aninclined surface,t convex surface, and/or a concave surface, for example. The second surface 899b can comprise a flat, or an at least substantially flat, surface, for example. In various instances, thefirst surface 899a and the second surface 8991) can convergeatanedlge899cforexamle. The barb 899 can be formed utilizing any suitable process. Forinstance, the barb 899 cani be formed utilizing a stamping process. In at least oneembodiment, a forming die, for example, can be utilized to strike the perimeter of the wire comprisingthe leg 804 in order toupset, or disturb, enough material to create the barb 899. In various embodiments, thewire comprising the staple can include oneornor-e flat sides. In at least one embodiment, the wire can include opposing flat sides 895, for example. In at least one such ermbodimet, the flat sides 895 can be formed into a cylindrical wire. In some instances, the wire can retain one ormore cylindrical surfaces in addition to the flat sides 895. In various instances, a barb can comprise any suitable nib or spur, for example. In various embodiments, the barb 899 can be tapered. In various instances, the barb 899 can include a base adjacent to the perimeter of the leg 804 which is thicker than a ip of the barb 899.

[0222] In various instances, the legs of a staple can define a staple plane. The base of the staple may or may not be positioed within the staple plane. in either event, one ormore barbs extending mrom the legs and/or the basemay extend within and/or extend parallel with respectto the staple plane. In sone instances, one or more barbs extending frort the legs and/or the base can extend outwardly from the staple plane. One orimorebarbs extending from the les and/or tiebase can extend transversely with respect to the staple plane. In various instances, a barb can extend circumferentially around a staple leg. Such a barb can extend within and outwardly From the staple plane. In some instances, a barb can extendaround the entire circumfderence ofa staple leg In certain instances, the barb can extend less than 360 degrees around a staple leg. A barb extending within a staple plane can readily control tissue within the staple plane. A barb extending outwardly from a staple plane can readily control tissue outside ofrte staple plane. A staple, and/ora staple leg, can include one or morebarbs extending within the staple plane and one or more barbs extending outwardly from the staple plane.

102231 Referring again to FI. 62, the barbs extending from a staple leg 804 can be configured to retain the staple leg 804 within tissue. As outline above, the staple legs 804 nay be alforied and/or unformed by an anvil in certain instances and, owing to the barb, or barbs, extending therefrom, the staple leg 804 may still be retained in thetissue In various instances, the barbs can be configured to trap tissue within the tissue entrapment area ofthe staple. In certain instances, the barbs can be configured tohold the tissue against the base 802. In such instances, the barbs can apply a compressive force or pressure to the tissue. As discussed above in connection with the eibodinents depicted in FIGS. 70-73, a barb can comprise an inclined, convex, and/or concavetop surface, such as surfaces 809a, 879a, 889a, and/or 899at, fo example The top surfaces ofthe barbs can be configured to facilitate the insertion ofthe barbs and the staple legs 804 into and/or through the tissue. As also discussed abovein connection with the eibodiments depicted inFIGS. 70-73, a barb can comprise a flat, or at least substantially flat, bottom surface, such as sIrfaces 809b, 879b, 889b, and/or 899b, for example, The bottom surfaces of Ie barbs can be conigured to inibit he removal ofthe barbs and the staple legs 804 from the tissue. As a result otfthe above, in certain circumstances, the top surfaces of the barbs can be conigured to pierce the tissue while hebottom surfaces of the barbs can be configured to abut the tissue. In various circumstances, the tips 806 of the staple legs 804 can be configured to picture a hole in the tissue while the staple legs 804 and the barbs extendingtherefrom can be configured to resiliently expand the hole such that such that the tissue can flow around the barbs as the staplelegs 804 are being pushed through the tissue and flow back underneath the boton surfaces of the barbs.

[0224] In certain embodiments, a first barb can extend from a first leg 804 of the staple and a second barb can extend from a second eg 804 ofthe staple. Invarious instances, the first barb and the second barbcan be located the same, or at least substantially the same, distance between from the base 802. In certain instances, the first barb and the second barb can be located the same, or at least substantially the same, vertical distance from the base 802. As discussed above, a staple leg 804 can include an array ofbarbs extending along the length of the staple leg 804. In various embodiments, referring primarily to FIG. 62, a staple can include a first leg 804 including a first array ofbarbs andasecond leg 804 including a second array of barbs wherein the first array of barbs and the second array ofbarbs can be configured to co-operatively hold the staple within the tissue. In various embodiments, a barb from the first array and a barb fromthe second array can comprise apair of barbs configured to engage tissue at the same vertical distance from the base 802, for example. In various instances, a staple can comprise more than one pair ofbarbs. In certain instances, each of thelbarb pairs can be configured to engage the tissue at a different vertical distance from the base802. In such circumstances, a staple cantibe suitable forusewith differenttissuethicktiesses. Forinstance,when a staple is used to staple thin tissue, one pair ofbarbs, or less than all of the barb pairs, may engage the thin tissue. If that staple were used to staple thick tissue, however, additional barb pairs, or all ofthe barb pairs, may engage the tissue. In certain embodiments, thebarbs extending from the legs 804 can be arranged in a mannerin accordance with the tissue thickness, orrange of tissue thicknesses, that can be stapled by the staple. ForinUstance, referring again to FIG. 62, tie barbs 808 and 809 can be selectively positioned along thelegs 804 such that they are positioned within and/or adjacent 1 the tissue captured within the staple. In certain instances, the portions of the staple legs 804 that are deformed by, or come into contact with, an anvil may not include barbs extending therefrom. In at least some instances, an array ofbarbs extending from the inwardly-facing side ofthe staple legs 804 iaybe longer than an array ofbarbs extendingfrom the outwardiv-facing side ofthe statelegs 804. In other instances, an array ofbarbs extending from the inwardly-facing side ofthe staple legs 804 may be shorter than an array of barbs extending from the outwardly-facing side of the staple legs 804. In yet otherinstances, an array of barbs extending from the inwardly facing side of the stapee 804may be the same length as an array of barbs extending frorn the outwardly-facing side of the stapeleaes 804.

[0225] As discussed above, thelbarbs extending from the staple legs 804 can assist in retaining the staple within the tissue if the staple legs 804 are malformedand/orunintentionallyunformed.Certain circumstances are contemplated, however, where a staple including one or more ofthe barbs disclosedherein is inserted intotissue and remains intentonallyunformed. In any event, staples including one or more of the barbs disclosed herein can be useful in stapling thick tissue. More particularly, in some instances, the presence of thick and/or dense tissue between a staple cartridge and an anvil and/or the presence of thick and/or dense tissue within a stapemay prevent thestaperom becoming fully formed or closed. Forinstance, the staple rav not be tilly closed into a B-form configuration or the staple may not be closed atall. in such instances, the barbs of iheunclosed staples may inhibit or prevent the tissue from being pulledout of the staple, for example. An array of barbs extending along the length of a staple leg may permit the ieg to remain retainedin the tissue regardless oFthe thickness or the tissue.

[0226] Various embodiments are contemplated in which at least one barbed staple, such as barbed staple 800, for example, are removably stored within a staple cartridge, such as the staple cartridge 22000 illustrated in FIGS. 10-12, for example. Certain embodiments are envisionedin which a staple cartridge includes only barbed staples while other embodiments are envisioned which utilize barbed staples and non-barbed staples. For instance, a First row ofstaples can comprise barbed staples while a second row of staples can comprise non-barbed staples. In some instances, the staples stored within a staple cartridge can have the same, or essentially the sati, unformed height. At least with regard to U-shaped and/or V-shaped staples, for example, tie unformed height of a staple can be defined as the vertical distancebetween thebottomofthebase ofthe staple and the tips ofthe staple legs.Suchameasurementcan be taken before the states areinserted into the staple cartridge, when the staples are removably stored within the staple cartridge, and/or before the staples are deformed against the anvil. In some instances, barbed staples arranged in first row in a staple cartridge ancompriseai rst unformedheight md barbed staples arranged in a second row in the staple cartridge can comprise a second unformed height. Barbed staples in a third row in the staple cartridge can comprise the first unformed height, the second unformed height, or a third unformed height. The first row, the second row, and/or the third row of barbed staples can be positioned on the same side of a knife slot defined in the staple cartridge or omopposite sides oftheknifeslot.Iuse,thebarbedstaplesremtovablystoredinastaplecartridgecanbe formed to the same formed height or different formed heights. The formed height of a staple can be defined as the overall vertical distance of the staple after it has been defonred against an anvil. At least with regard to a staple that has been deformedinto a B--fortn, for example, the formed height of the staple can bemeasured between the bottom of thebaseofthestapleandthetop-mostportio ofth staple legs. In some instances, barbed staples arrangedinafirst row in a staple cartridge can be deformed toa nrst formed heightand barbed staples atanged in a second row in the staple cartridge can be deformed to a second formed height. Barbed staples in a third row in the staple cartridgecan comprisethe first formed height, the second formed height, or a third formed height. The first row, the second row, and/or thethird row of barbed staples can be positioned on the same sideofaknifcotdenedinthestaplecartridge or on opposite sides of the staple cartridge. As the readerwill appreciate, the staples depicted FIGS. 10-12 have been deformed to different formed heights. Barbed staples 800, for example, could be utilized in staple cartridges and/or staplin instruments which create staple rowslhaving different fored heights. A firstrow of barbed staples 800 could be deformed to a rstformedheight and a second row of barbed staples 800 could be deformed to a second formed height. In various instances, a third row of barbed staples 800 could be deformed to a third formed height. In some instances, the barbed staples 800 deformedto different heights can begin with the same, or essentially the same, unformedheight. In certain instances, the barbed staples 800 deformed to different formed heights can begin with different unformed heights. Variousstructurescan beutilized to form staplesto differentformedheights. For tristance, movable drivers supporting the staples can support the staples at different distances relative to the anvil. In someinstances, the anvil can include staple forming pockets having different depths. ITvarious instances, a staple driver can include a cradle configured to support the base of a staple and push the staple upwardly toward a forming pocket defined in the anvil. The foned height of a staple can be determined by the distance between the bottom surface ofthe cradle and the top surface of the forming pocket. U.S. Patent No. 8,317,070, entitled SURGICAL STAPLING DEVICES THAT PRODUCE FORMED STAPLES HAVING DIFFERENTLENGTHS, issued on November 27, 2012, is incorporated by reference in its entirety. In certain instances, the deck of a staple cartridge can include stepped surfaces, as illustrated inFIG 1, A firstrow of staple cavities can be defined in a firststep and a second row ofstaple cavities can be definedin a second step wherein the first step and the second step can be vertically offset from one another. For instance, the first step can be positioned vertically above, or closer to, the anvil than the second step. In certain instances, a wall can be defined between the first step and the second step. In some instances, the deck ofa staple cartridge can comprise a first step, a second step positioned vertically above the first step, and a third step positioned vertically above the second step. Various embodiments are envisionedin which the deck ofa staple cartridge includes any suitable number of steps and any suitable umber ofwalls between the steps. A first row of staple cavities can be definedin the first step, a second row of'staple cavities can be defined in the second step, and/or a third row of staple cavities can be defied in the third step, for example. The first row of staple cavities car include staples having a first unformed height, the second row of staple cavities can include staples having a second unformed height, and/or the third row of staple cavities can iclude staples having a third unformed height, for example.i Varios embodiments are envisioned in which a staple cartridge includes any suitable number of staple rows having different unformed heights. The staples in the first row of staple cavities can be deformed to a first formed height, the staples in thesecondrow of staple cavities can be deformed to a second formed height, and/or the third row of stale cavities can be deformed to a third formed height, for example. Various embodiments are envisioned in which a staple cartridge includes any suitable number of staple rows which are deformed to different formed heights. In addition to or in lieu of having different formed staple heihits, an end effector ofa stapling instrumentcan have different tissue gaps. For instance,referring generall toFIGS. 10 and II., a gap can be defined between the cartridge deck surface 22011 of a staple cartridge and the anvil tissue compression surface 10063 of an anvil. This gap can be configured to receive tissue T. This gap can also he configured to receive a tissue thickness compensator; however, a barbed staple may or may not be used with a tissue thickness compensator andthe discussion provided with respect to barbed staples can be applicable in either circumstance. In any event, the reader will appreciha t the anvil tissue compression surface 10063 is stepped. The anvil tissue compression surface 10063 conrises a first portion positioned vertically above a second portion. When the anvil and the staple cartridge of an end effector are in closed condition, as illustrated in FIG. I 1, a first gap distance is defined between an outer portion ofthe anvil tissue compression surface 10063 and the cartridge deck surface 22011 and a second, different, gap distance is defined between an inner portion oftheanvil tissue compression surface 10063 and the cartridge deck surface22011. The first gap distance is illustrated as being larger than the second gap distance, but it is possible for the firstgap distance to be shorter than the second gap distance. Tissue compressed between the anvil and the staple cartridge in the shorter can distance can be compressed more than tissue in the larger gap distance. Thebarsofa barbed staple 800, for example, may engage the tissue differently depending onwhether the tissue is positioned within shorter tissue gap oi a larger tissue gap. More particularly, tissue compressed within a shorter tissue gapmay seek to re-expand more after it is released from an end effector than tissue compressed within a larger tissue gap and the barbs of a barbed sape mrna inhibit or resist this re-expansion, depending on their confiuration and/or position on the barbs. In otier instances, the barbs may be configured and/or positioned so as to not inhibit or resist the re-expansion of the tissue. As the reader will appreciate, anvil tissue compression surface 10063 is stepped and the cartridge deck surface is flat, or at least substantially flat, and, thus, the difference in tissue gaps defined within tie end effector is a function of the heigt othe stepped anvil surfaces, Other embodiments are envisioned. For instance, the anvit tissue compression surface canbe flat, or at least substantially flat, and the cartridge deck surface can be stepped. In other instances, the anvil tissue compression surface and the cartridge deck surface can both be stepped. In any event, different gap distances can be defined between the anviltissue compression surface and the cartridge deck surface. While twogap distances have bee illustrated in FIGS. 10 and 11, more than two gap distances may be possible, such as three gap distances, for example. With further reference to FIGS. 10 and 11, a first longitudinal row of forming pockets can be arranged within a finest portion of an end effector havingfirst tissue gap distance and a second longitudinal row of forming pockets can be arranged within a second portion ofthe end effector having a second tissue gap distance which is different than the first tissue gap distance. In some instances, the end effector can include a third longitudinal row of forcing pockets atrrniged within aithurd portion of the end effectorlhaving a third tissue gap distance which is different than tie first tissue gap distance and the second tissue gap distance. In certain instances, theend effiector can include a thirdlonigitudinal row of forming pockets arranged within a third portion of the end effectorhaving a tissue gap distance which isthe same as the first tissue gap distance orthe second tissue gap distance. The reader will appreciate that an end effector can have different tissue gap distances and/or different formed staple heights. An end effector can have one, the other, orboth,. In certain instances, shorter formed staple heights can be associated within shorter tissue gap distances while larger formed staple heights can be associated with larger tissue cap distances In otherinstances, shorter formed staple heights can beassociated with larger tissue gap distances while larger formed staple heights can be associated with shorter tissue gap distances. Furtherto the above, a staple can include a U-shape configuration in its unforined state.AU-shapestaplecancompriseabaseandtwo staple legs extending from the base wherein the staple legs extend in parallel directions to each other. Also further to the above, a staple can include a V-shape configuration in its unformed state. A V-shape con fguration can comprise a base and two staple legs extending from the base wherein the staple legs extend in directions which are not parallel.

[0227] Various embodiments described herein are described in the context of linear end effectors and/orlinear astener cartridges. Such embodiments, and the teachings thereof, can be applied to non-linear end effectors and/or non-linear fastenercartridges, such as, for example, circular and/or contoured end effectors. For example, various end effectors, including non-linear end effectors, are disclosed in U.S. Patent Application Serial No. 13/036,647, filed February 28, 2011, entitled SURGICAL STAPLINGINSTRUMENT,now U.S. Patent Application Pubication No. 2011/0226837. whichis hereby incorporated by referencein its entirety. Additionally, U.S. Patent Application Serial No, i2/893,461, filed September29, 2012, entitled STAPLE CARTRIDGE, now U.S. Patent Application Publication No. 2012/0074198, isherebyincorporated byreference in its entirety. U.S. PatentApplication Serial No. 12/031,873, filed February 15, 2008, entitled END EFFECTORS FOR A SURGICAL CUTTING AND STAPLING INSTRUMENT, now U.S. Patent No. 7980,443, is also hereby incorporated by reference in its entirety. The entire disclosure of U.S. Patent No. 7,845,537, entitled SURGICAL NSTRUMNT HAVING RECORDING CAPABILITIES, which issued on December'7, 2010, is incorporated byrefJerenceherein. The entire disclosure oF U.S. Application Serial No. 13/118,241, entitled SURGICAL STAPLING INSTRUMENTS WITH ROTATABLE STAPLE DEPLOYMENT ARRANGEMENTS, now U.S. PatenttApplicatiot Publication No. 2012/0298719, which was filed on May 27, 2011, is incorporated by reference herein.

[0228] The devicesdisclosed herein canbe designed to be disposed of after a single use,orthey can be designedto be used multiple times. In either case, however, the device can be reconditioned foreuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, the device can be disassembled, and any number of the particular piecesor parts ofthe device can be selectively replaced or removedin any combination. Upon cleaning and/or replacement of nartiular parts,the device can be reassembled for subsequentuse either at a reconditioning facility, or by a surgical team immediatelyprior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety oftechniques for disassembly, cleaning/replacement, andreassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

[0229] Preferably, the invention described herein will be processed before surgery. First, aneworiused instrument isobtained and if necessary cleaned. The instment ca then be sterilizedIn one sterilization technique, the instrumentis placed in aclosed and sealed container, such as a plastic or TYVEK bag. Thecontainerandinstriument are then paced in a field of radiation that can penetrate the container, such as annia radiation, x-rays, orhigh-energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrunent can then be stored in the sterile container. The sealed container keeps the instrument sterile until it is opened in themedical facility.

[0230] Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by referencefherein is incorporated herein only to the extent tha the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extentnecessary. the disclosure as explicitly set forth herein sup.ersedes any conflicting material incorporated hereinlby reference. Any material, or tion thereofth at is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

[0231] Whbile this invention has been described as having exemplary designs, the present invention may be further modified within the spirit and scope ofthe disclosure. This application is thereforeintended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to coversuch departures from the present disclosure as come within known or customary practice in the art to which thisinvention pertains.

Claims

WHAT IS CLAIMED IS:

1. An end effector for fastening tissue, comprising: an anvil, wherein said anvil comprises a deck configured to support tissue, wherein said deck comprises:

a first surface, having a first longitudinal row of staple forcing pockets; and

a second surface, having a second longitudinal row of staple forming pockets, and wherein said first surface is positioned vertically above said second surface;

a cartridge comprising a plurality of staple cavities, wherein said plurality of staple cavities are arranged in first and second longitudinal rows of staple cavities;

a plurality of staples removably stored within said staple cavities, and a plurality of staple drivers movable within said staple cavities, wherein said staple drivers are configured to lift said staples toward said anvil, each said staple comprises, a base, a pair of legs extending from said base wherein each said leg has a tip configured to pierce tissue, and wherein each said leg comprises at least two barbs extending from each said leg inwardly toward a center of said staple; and

a firing member configured to lift said staple drivers toward said anvil, wherein said firing member comprises a first portion configured to engage said anvil and a second portion configured to engage said cartridge, and wherein said firing member is configured to relatively position said anvil and said cartridge.

2. An end effector for fastening tissue, comprising: an anvil comprising a tissue compression portion configured to support tissue, said tissue compression portion comprising:

a first compression surface, and a first longitudinal row of staple forcing pockets defined in said first compression surface;

a second compression surface, and a second longitudinal row of staple forming pockets defined in said first compression surface;

a longitudinal slot configured to receive a cutting member, wherein said longitudinal slot divides said tissue compression portion into a first lateral side and a o second lateral side, wherein said first compression surface and said second compression surface are positioned on said first lateral side of said longitudinal slot, and wherein said first compression surface is offset from said second compression surface; and a cartridge, comprising: a first deck portion alignable with said first compression surface; a second deck portion alignable with said second compression surface; and a plurality of staple cavities, wherein said plurality of staple cavities are arranged in a first longitudinal row of staple cavities and a second longitudinal row of staple cavities, wherein said first longitudinal row of staple cavities are defined in said first deck portion, wherein said second longitudinal row of staple cavities are defined in said second deck portion, wherein a first gap distance is defined between said first compression surface and said first deck portion, wherein a second gap distance is defined between said second compression surface and said second deck portion, and wherein said first gap distance is different than said second gap distance; a plurality of staples removably stored within said staple cavities, wherein each said staple comprises: a base; and a plurality of legs extending from said base, wherein each said leg comprises a tip configured to pierce tissue, and wherein each said leg comprises at least two barbs extending from said legs inwardly toward a center of said staple; a plurality of staple drivers movable within said staple cavities, wherein said staple drivers are configured to lift said staples toward said anvil; and a firing member configured to lift said staple drivers toward said anvil, wherein said firing member comprises a first portion configured to engage said anvil and a second portion configured to engage said cartridge, and wherein said firing member is configured to relatively position said anvil and said cartridge.

3. The end effector of Claim 1 or 2, wherein said firing member comprises a knife edge.

4. The end effector of Claim I or 2, wherein said firing member comprises at least one inclined surface configured to lift said drivers toward said anvil.