US2367439A - Matrix retainer - Google Patents

Description

Jan. 16, 1945. Q Q s R 2,367,439

MATRIX RETAINER Filed Jan. 11, 1943 INVE OR.

24 /7 25 BY M5 50 A TTOR/VZ'MS.

Patented Jan. 16, 1945 MATRIX RETAINER Orin C. Samphere, West Allis, Wis.

Application January 11, 1943,- Serial No. 472,009

6 Claims. (01. 32-63) The present invention relates generally to improvements in the art of dentistry, and relates more specifically to improvements in the construction and operation of dental instruments of the type known to the profession as matrix retainers.

An'object of this invention is to provide an improved matrix ribbon clamp and retainer which is simple and compact in construction, and which is moreover highly efiicient in use.

It has long been common practice in the 'art of dentistry, to fill cavities in teeth by first properly preparing each cavity, thereafter snugly surrounding the tooth and cavity with a flexible metallic strip known as a matrix ribbon, then inserting the filling or impression wax, and by finally removing the matrix ribbon and finishing the filling. These matrix ribbons are highly flexible in order to cause them to readily conform. with the contour of the teeth-embraced thereby, and were ordinarily clamped about the selected teeth. with the aid or a matrix retainer having. a screw adjustment for producing the desired clamping action. While these. prior matrix retainers are quite eliective when applying and clamping a flexible ribbon about a cylindrical body having a recess in the side thereof, they are not well adapted to cause such a ribbon to snugly embrace a tapered object such as a molar or bicuspid tooth; and when the ordinary matrix used on the molars which usually taper abruptly toward'the' roots and are also comparativelyinaccessible for application of'thesespecial matrix strips. over could not be readily dismantled for-inspection and cleaning, and were therefore rather unsanitary in use.

The. present invention therefore contemplates the provision of.an improved clamp and retainer whereby 'fiexible matrix ribbons orthe like may bequickly. andefliectively applied "to even the most abruptly tapered teeth, so as to avoid. shoulders or oil-sets at the edges. of fillings and to provide smooth contours for the; filled teeth- The prior matrix ribbon retainers more- Another pecific object of this invention is to;

provide an improved matrix ribbon clampingolevice which is adapted for either manual or auto matic adjustment so as to cause an ordinary matrix strip to properly coact with irregular and tapered teeth at all edges of lateral relatively inaccessible cavities therein.

A further specific object of my invention is to provide a new and extremely useful and efiicient matrix retainer, which can be quickly dismantled for inspection and cleaning, and thereafter 1 readily reassembled, and which may therefore be kept in highly sanitary condition.

Still another specific object of theinventionr of constructing'and of manipulating one of the improved: matrix retainers, may be had by. refering to the drawing accompanying and form-' ing a part of this specification wherein like reference characters designate the same or similar parts inthe variousviews.

Fig. 1 is a part sectional top view of several normal teeth or a lower jaw, showing one of the improved matrix retainers partially in section. cooperating with a matrix ribbon applied to one of the bicuspids;

Fig. 2 is an inside elevation of the assemblage of Fig; 1;

Fig. 8 is an outside elevation of the assemblage of Figs. 1 and 2; r:

Fig. 4 is an enlarged fragmentary centrallongitudinal section through one of the improved matrix: retainers;

Fig. 5 is a similarly enlarged fragmentary in-' net side view of the ribbon carrying end of the a instrument, showing the adjustable ribbon guides cially adapted to cooperate with highly flexible ways II of the frame 8 and having a rigid ribbon clamping abutment I3 at one end, and an integral wall I4 at its opposite end provided with a threaded opening I5; clamping rod I6 having one end cooperable with the slide abutment I3 to firmly clamp the ends of a piece of matrix ribbon I'I thereagainst, while its opposite end is provided with a manipulating knob or handle I8, and its medial screw-threaded portion coacts with the threaded slide opening I5; an adjusting nut I9 for the slide I2, coacting with the screw threads of the rod IS and having a reduced circular portion or annular groove 20 normally journalled in the bifurcation 2| of the frame wall Ill; and a pair ofangularly adjustable ribbon guides 22, 23 which are swingably adjustably suspended from the frame 8 near the slot 9 by means of pivot screws 24, 25 respectively.

The frame 8 and slide I2 may be formed of suitable sheet material, preferably metal, with the aid of punches and dies, and the opposite sides of the elongated frame 8 are provided with integral flanges 26portions of which are bent inwardly toward each other to form the guideways II. The slide I2 is movable between these side flanges 26 and along the guideways I I by the nut I9 coacting with the screw threads of the rod I 6 and which is journalled for rotation in the bifurcation 2| of the frame end wall Ill; and while the threaded rod I6 has screw thread coaction with the opening I5 of the slide wall I4, it has no such screw thread coaction with the abutment or clamping end of the slide I2 but is merely freely rotatable within the opening 2! of the slide as shown in Fig. 4.

The threaded clamping and adjusting rod I8 is preferably of sufiicient length, so that continued rotation of the ribbon tensioning nut I9 in the proper direction, will ultimately cause the slide I2 to leave the free end of the guideways II as in Fig. 6, whereupon the nut I9 may be freely removed from the bifurcation 2| and the rod and: slide assemblage may be removed from the frame 8. The rod I6 may also be readily removed from the slide I2 and nut I9, by merely rotating the rod I6 relative to these parts with the aid of the handle I8, thus permitting thorough cleansing and sterilization of all parts. and the elements may obviously be readily reassembled in an obvious manner.

The matrix strip or flexible ribbon I7 is ordinarily formed of thin metal and may be of any predetermined or selected length dependent upon the size of the tooth 28 having a cavity 29 therein which is to be filled, and the ends of the ribbon pass through the opening or slot 9 in the frame 8 and may be firmly clamped against the slide abutment I3 as illustrated in Figs. 1. and 4. The ribbon I'I passes between the adjustable guides 22, 23 and is adapted to coact with curved flanges 30 formed integral with these guides so as to eliminate sharp bends; and the two guides an elongated threaded 22, 23 are independently pivotally adjustable about their respective retaining screws 24, 25. These screws 24, 25 may be utilized to either fixedly position the guides 22, 23 in any desired angular position as shown in Fig. 5, or they may be left loose enough so that the guides will automatically assume various angular positions, but in either case they will by proper setting cause the loop of the ribbon I! to snugly coact with objects such as teeth 28 having different tapers or contours.

The improved matrix retainer is applicable to any of the molars or bicuspids of either jaw, and has been shown applied to one of the bicuspids in Figs. 1 to 3 inclusive. During normal use of the instrument, the dentist should first prepare the cavity 29 for reception of the filling and should select a piece of matrix ribbon I! of sufficient length to embrace the tooth 28 which is to be filled. The ends of the flexible ribbon I! may then be inserted through the frame slot 9 while the slide abutment I3 is disposed adjacent to this slot, and the extreme ends of the ribbon can then be firmly clamped to the abutment by rotating the clamping rod I6 within the opening I5 of the wall I4. After this clamping of the ribbon ends has been effected, the nut I9 may be rotated to move the slide I2 along the guideways I I toward the frame end wall III and away from the opening or slot 9, thereby diminishing the size of the ribbon loop. The pivot screws 24, 25 for the guides 22, 23 may then be loosened to permit pivotal swinging of these guides. and these screws may either be left in J loosened condition so as to permit automatic shifting of the guides 22, 23, or they may be tightened after the guides have been set to conform with the taper of the tooth 28 which is to be treated, so as to hold the ribbon guiding flanges 30 in fixed position.

The loop of the ribbon I1 may then be slipped over the tooth 28 to a position closely adjoining the gum 3|, whereupon the nut I9 should be rotated so as to shift the slide I2 away from the slot 9. This adjustment of the slide I2 will cause the ribbon loop to be drawn snugly about the tooth 28 and cavity 29, and the guide flanges 30 will effectively cause the flexible ribbon I! to hug the tapered exterior of the tooth and to thoroughly seal the bottom of the cavity 29 regardless of the shape or degree of taper of the tooth 28. The filling material or impression wax may then be inserted within the cavit 29 and will be prevented by the ribbon II from extension beyond the tapered side of the tooth 28, and after the inserted material or wax has set. the nut I9 may again be manipulated to move the slide I2 awa from the frame wall I0 and toward the slot 9, thereby releasing the ribbon tension and enlarging the loop of the ribbon I1 sufficiently to permit free withdrawal thereof from the tooth 28.

After a tooth 28 has been thus filled with the aid of the improved device, the slide I2 may again be positioned with the abutment I3 thereof over the slot 9, and the screw I 6 may be rotated relative to the slide wall I4 and opening I5 so as to release the ribbon ends. The used ribbon I! may then be removed, whereupon the slide I2 and rod I6 together with the nut I9. may be completely removed from the frame 8 as shown in Fig.. 6, for cleaning and "sterilization. When cleansing has been effected, the parts may be quickly and readily reassembled so as to place the implement in condition for subsequent use,

and the entire manipulation is obviously very simple.

From the foregoing detailed description of the construction and operation of the improved matrix retainer, it will be apparent that the present invention provides an implement which will permit rapid and effective application of a flexible matrix ribbon to even the most abruptly tapered teeth, in a manner which will avoid shoulders or off-sets at the edges of the cavities and fillings. The improved matrix ribbon clamping device is obviously adapted for either manual or automatic adjustment of the guides 22, 23 so as to cause the flexible matrix strip or ribbon H to properly coact with the irregular and tapered bodies of the teeth 28 at all edges of the cavities 29. The improved implement may moreover be conveniently and quickly dismantled for cleaning purposes, and may be just as quickly reassembled for subsequent use, and the several parts of the improved ribbon clamp and retainer ma obviously be manufactured from relatively inexpensive materials and with the aid of simple equipment. My improved matrix retainer has proven highly satisfactory in actual use, and can be manipulated by inexperienced persons so as to produce most effective results with minimum loss of time.

It should be understood that it is not desired to limit this invention to the exact details of construction or to the precise mode of use of the specific device herein shown and described, for various modifications within the scope of the appended claims may occur to persons skilled in the art.

I claim:

1. In combination, an elongated frame having a transverse slot, a slide movable along said frame, a rod extending along said frame and coacting with said slide and being adapted to clamp the ends of a flexible ribbon to the slide so as to form a tooth embracing loop adjacent to the frame and extending outwardly through said slot, adjusting means coacting with said rod and frame for moving said slide to vary the siz of said loop, and a pair of movable ribbon guides carried by said frame on opposite sides of said slot and coacting with the ends of the loop, said guides being relatively angularly adjustable to cause said loop to assume a taper conforming with the taper of the tooth to which the loop is snugly applied.

2. In combination, a frame having a transverse slot, a slide movable relative to said frame, a threaded rod coacting with said slide and being adapted to clamp the ends of a flexible ribbon to the slide so as to form a loop extending laterally from said frame and outwardly through said slot, a nut journalled in said frame and coacting with the screw threads of said rod to move said slide relative to said frame, and automatically adjustable guides swingably suspended from said frame on opposite sides of said slot and coacting with the ends of the loop to cause said loop to assume a definite laterally tapered formation when the same is drawn into snug engagement with a tapered tooth.

3. In combination, a frame having a transverse slot, means carried by said frame and being adapted to clamp the ends of a piece of flexible ribbon to form a tooth embracing loop disposed near an end of the frame and extending outwardly through said slot, adjusting means coacting with said frame to vary the size of said loop, and a pair of spaced and freely relatively angularly adjustable guides carried by said frame on opposite sides of said slot and coacting with said ribbon between its clamped ends and said loop for causing the ribbon loop to assume a definite laterally tapered formation when the loop is drawn into snug embracing engagement with a tapered tooth.

4; In combination, an elongated frame having .tooth to which the loop is snugly applied.

5. In combination, an elongated frame having a transverse slot near one end and guideways extending away from'said slot, a slide movable along said guideways, a rod coacting with said slide and being operable to clamp a flexible ribbon to the slide so as to form a loop extending outwardly through said slot, means coacting with said frame and rod to move said slide along said guideways away from said slot and to thereby diminish said loop, and a guide swingably suspended from said frame on each side of said slot and coacting with the adjacent end of the loop,

' said guides being relatively angularly displaceable to cause the loop to assume the taper of the tooth about which the loop is snugly drawn when said slide is moved away from said slot,

6. In combination, a frame having a transverse slot, a slide movable'along said frame, a rod coacting with said frame and slide to move the latter relative to said slot, means for fastening a matrix ribbon to said rod and slide to form a loop extending outwardly through said slot, means for moving said rod to diminish the size of said loop, and a guide pivotally attached to said frame on each side of said slot and coacting with the adjacent end of the loop, said guides being relatively angularly displaceable to caus the loop ribbon to snugly embrace teeth of diverse tapered formations.

ORIN C. SAMPHERE.

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