US3868776A - Removable dental bridge and method for making same - Google Patents

Abstract

A patient-removable dental bridge includes a male support member mounted on an abutment tooth to serve as a bridge support, and a female mounting member embedded in an artificial tooth and including a socket to be releasably engaged with the male member. The male member is a solid piece extending about one-half the width and the entire height of the artificial tooth. A narrow and shallow notch is located in the top edge of the male support member, preferably near the corner adjacent the abutment tooth. A transverse bridge piece in the top of the female member fits into the notch when the two members are engaged to act as a stop against movement of the artificial tooth into the gum tissue. A tension bar disposed between the male and female members provides proper tension between the two members and can be adjusted to compensate for wear. The two members are made by trimming plastic male and female dies into the desired shapes. The male support member is cast in metal from the male die, and the female die is then fitted onto the cast male member to facilitate forming the bridge piece. The female mounting member is then cast in metal from the plastic female die. Alternately, the artificial tooth includes a cast metal occlusal cap fitted over the top of a female socket member which is preferably made of plastic. The occlusal cap provides a bridge piece which fits into the notch of the male member. The balance of the artificial tooth is formed in an acrylic material which bonds the occlusal cap to the female socket member.

Description

United States Patent Lasky Mar. 4, 1975 REMOVABLE DENTAL BRIDGE AND METHOD FOR MAKING SAME [76] Inventor: Mervyn CuLasky, i535 N.

Poinsettia Pl., Hollywood, Calif. 90046 [22] Filed: June 26, 1974 [21] Appl. No.: 483,164

Related U.S. Application Data [63] Continuation-impart of Ser. No. 334,729. Feb. 22,

[52] U.S. Cl. 32/5 [51] Int. Cl. A6lc 13/22 [58] Field of Search 32/5, 6

[56] References Cited UNITED STATES PATENTS 3 59342O 7/1971 Ritter 32/5 3.660.899 5/1972 Linkow 32/5 Primary E.\aminer-Robert Peshock Attorney, Agent, 0'- Firm-Christie, Parker & Hale [57] ABSTRACT A patient-removable dental bridge includes a male support member mounted on an abutment tooth to serve as a bridge support, and a female mounting member embedded in an artificial] tooth and including a socket to be releasably engaged with the male member. The male member is a solid piece extending about one-half the width and the entire height of the artificial tooth. A narrow and shallow notch is located in the top edge of the male support member, preferably near the corner adjacent the abutment tooth. A transverse bridge piece in the top of the female member fits into the notch when the two members are engaged to act as a stop against movement of the artificial tooth into the gum tissue. A tension bar disposed between the male and female members provides proper tension between the two members and can be adjusted to compensate for wear. The two members are made by trimming plastic male and female dies intothe desired shapes. The male support member is cast in metal from the male die, and the female die is then fitted onto the cast male member to facilitate forming the bridge piece. The female mounting member is then cast in metal from the plastic female die. Alternately, the artificial tooth includes a cast metal occlusal cap fitted over the top of a female socket member which is preferably made of plastic. The occlusal cap provides a bridge piece which fits into the notch of the male member. The balance of the artificial tooth is formed in an acrylic material which bonds the occlusal cap to the female socket member.

10 Claims, 13 Drawing Figures REMOVABLE DENTAL BRIDGE AND METHOD FOR MAKING SAME CROSS-REFERENCE TO RELATED APPLICATION This is a continuation-in-part of my pending application Ser. No. 334,729, filed Feb. 22, 1973.

BACKGROUND OF THE INVENTION This invention relates to dental bridges, and more particularly to a semi-fixed patient-removable bridge, and a method of making such a bridge.

There are several advantages of patient-removable dental bridges, the major advantage being that the patient can periodically remove the artificial tooth, or pontic, to cleanse the abutment tooth, the gum tissue in the area of the pontic and the pontic itself. Conversely, fixed bridges can be a source of trouble for the patient, because food particles become trapped between the pontic and the surrounding gum tissue. Since the trapped food particles are virtually impossible to remove, over a period of time they decay andcan cause irritation or inflammation of the gum tissue, which eventually can cause pyorrhea and recurrent decay.

Other advantages of patient-removable bridges over I fixed bridges include easy access to all teeth in the area of the pontic when the pontic is removed, and substantially simplified repair work required of the dentist if any trouble develops in the abutment teeth or pontics.

My US. Pat. No. 3,171,202 discloses a patientremovable dental bridge which generally includes a U- shaped male support member rigidly secured to an abutment tooth. A female mounting member embedded in the artificial tooth has a U-shaped socket releasably fitted over the male member to hold the artificial tooth next to the abutment tooth. Although the bridge disclosed in my patent has proved to be successful in use, it has several disadvantages which are overcome by the improved bridge attachment of the present invention. It will become clear from the description below that the attachment of this invention is substantially stronger than my previous bridge in resisting the stress exerted on the bridge members during use. This substantially prevents breakage of the attachment members during use. The present dental bridge also is simpler in construction than the previous bridge, which reduces manufacturing time and costs, as well as reducing the chances of manufacturing bridge attachments susceptible of premature breakage.

SUMMARY OF THE INVENTION Briefly, the dental bridge attachment of this invention includes a male support member to be mounted on an abutment tooth to serve as a bridge support, and a female mounting member rigidly secured to a pontic and having a socket shaped to be releasably fitted on the male member. The male member is a solid piece extending mesio-distally from the abutment tooth preferably for about one-half the width of the pontic. The solid piece has a pair of spaced apart, upright first and second edges which extend occluso-gingivally substantially the entire height of the pontic, and a top edge extending between the first and second edges. The top edge traverses a major portion of the width of the male member, with the remaining portion of the top edge being recessed to form a narrow, relatively shallow notch in the top of the male member, The depth of the notch extends for a minor portion of the height of the male member.

The socket formed by the female member includes spaced apart lingual and facial surfaces to be engaged with opposite sides of the male member, and a bridge piece connecting the tops of the lingual and facial surfaces. The bridge piece is shaped to match the contour of the notch in the male member, and makes a tight fit in the notch when the male and female members are releasably secured to each other. In one form of the invention, the lingual and facial surfaces and the bridge piece of the female member are all cast as an integral unit.

In another form of the invention, the female member includes an occlusal cap which is fitted over the top of a female socket member that provides lingual and facial surfaces for abutting against the opposite sides of the male member. The occlusal cap provides the bridge piece for fitting into the notch of the male member. The occlusal cap can be cast from a relatively inexpensive metal such as chrome, and the female socket member can be made of plastic. The balance of the artificial tooth can be formed from an acrylic material which bonds the socket member and occlusal cap together as a unit. This form of the invention is especially suitable for relatively low cost manufacture of the artificial tooth. The ever-increasing cost of precious metals such as gold has made the cost of casting bridge attachments and inlays in gold almost prohibitive. In the past the use of a less expensive metal such as chrome for inlays and certain bridge attachments has not proven practical because of the difficulty in making chrome castings accurately enough to fit the teeth. However, in the present invention only the occlusal cap need be made of metal and does not have to absolutely fit the size and shape of the tooth. Therefore, the occlusal cap can be made from chrome. The remaining portion of the artificial tooth can be made of plastic, and the result is a relatively inexpensive patient-removable dental bridge.

In use, the cooperating notch and bridge piece act as an occlusal stop to prevent movement of the pontic into the gum tissue. The male member provides a relatively long and wide solid support for the pontic, which substantially prevents breakage of the attachment members when compared with prior art removable bridges. 7

In a preferred form of the invention, the notch is near the top corner of the male member adjacent the abutment tooth. This reduces substantially the stress exerted on the attachment members during use, because the leverage acting on the bridge piece during use is minimized clue to the support provided for the bridge piece by the adjacent abutment tooth.

Preferably, the male member includes an upright shoulder located remote from the abutment tooth. The female member includes an elongated channel which engages the shoulder when the two members are connected. This construction provides added stability for the attachment, and keeps the teeth from drifting apart mesio-distally during use.

A tension bar preferably is disposed between the male and female members when the pontic is in place to provide proper tension between the two members. The tension bar can be adjusted to compensate for wear between the two members.

BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects of the invention will be more fully understood by referring to the following detailed description and the accompanying drawings in which;

FIG. 1 is an exploded elevation view, partly in section, showing male and female attachment members of a prior art removable bridge;

FIG. 2 is an exploded elevation view, partly in section, showing male and female attachment members of a removable bridge according to this invention;

FIG. 3 is a schematic exploded perspective view showing the detailed construction of the male and female attachment members of this invention;

FIG. 4 is a schematic perspective view showing the male and female members of FIG. 3 in their engaged position, and also showing a tension bar on the lingual side of the attachment;

FIG. 5 is a schematic perspective view of the male and female members engaged in an alternate configuration in which the tension bar is located at the end of the attachment remote from the abutment tooth;

FIG. 6 is an exploded perspective view showing male and female dies to be used in forming the attachment members of this invention;

FIG. 7 is a schematic perspective view showing two male members releasably engaged with a double female mounting member, and also showing a U-shaped tension bar at the interface between the two male members;

FIG. 8 is a schematic elevation view taken on line 7-7 of FIG. 7;

FIG. 9 is a schematic perspective view showing an alternate configuration of the attachment in FIG. 7 in which a pair of tension bars are located on the lingual side of the attachment;

FIG. 10 is an exploded fragmentary elevation view showing an alternate embodiment of the male and female attachment members of the removable bridge according to this invention;

FIG. 11 is an exploded elevation view, taken on line 11-11 of FIG. 10,

FIG. 12 is a plan view taken on line 12l2 of FIG. 10; and

FIG. 13 is a schematic elevation view showing a completed artificial tooth containing the male and female attachment members shown in FIGS. 10 through 12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a prior art patient-removable bridge 10 of the type disclosed in my US. Pat. No. 3,171,202 mounts a pair of side-by-side artificial teeth or pontics (represented schematically at 12) in the space between a right natural tooth abutment 14 and a left natural tooth abutment 16. The removable bridge includes a generally U-shaped right male support member 18 soldered to an inlay 20 in abutment tooth l4, and a generally U-shaped left male support member 22 soldered to an inlay 24 in the left abutment tooth. Each male member includes a narrow upright leg 26 at the end thereof remote from the abutment tooth. Leg 26 is spaced from an attachment portion 28 of the male member by a narrow, longitudinally extending slot 30.

Bridge 10 also includes a pair of side-by-side right and left female mounting members 32 and 34, respectively. A longitudinally extending bridge member 36 interconnects the adjacent upper corners of the two female members. Each female member is embedded in a respective pontic l2, and each member forms a U- shaped socket adapted to slip releasably over a corresponding one of the male members to mount the two pontics in the space between the right and left abutment teeth. Each female member includes opposed, narrow, elongated recessed faces 38 to be engaged in slot 28 of the male member, and inwardly extending abutment ridges 40 at the bottom of the recess on the lingual and facial sides of the female members. Ridges 40 rest on the bottom of slot 28 to limit gingival movement of the bridge.

There are several disadvantages of the prior art bridge 10 which are overcome by the present invention. For example, leg 26 of the male member is relatively thin, and a substantial amount of leverage is exerted on it during use because it is located at the furthest remote point from the members point of support on the abutment tooth. Because of these factors, leg 26 is prone to breakage, usually at its base, due to the constant force exerted on it during use.

The prior art male member also requires the use of extreme care during manufacture. There is a likelihood that leg 26 sometimes will be ground too thin, thereby increasing the chances of breakage. There is also a likelihood that slot 30 will be ground too deep, leaving too thin a bridge 42 at the base of the member between leg 26 and attachment portion 28. Substantial stress is concentrated at bridge 42 during use, because forces from chewing are transferred to the bottom of slot 30 by abutment ridges 40 of the female member, and because of the leverage due to the remote location of bridge 42 from the male members point of support on the abutment tooth. Because of this stress concentration, there is an increased chance that the member will break at the base of slot 30 in the event bridge 42 is ground too thin. To prevent such breakage requires extreme care during grinding which, in turn, makes the manufacturing process for the attachment costly, time consuming, and wasteful of material.

The problems associated with prior art bridges 10 are overcome by a removable bridge or attachment members 44 shown in FIGS. 2 and 3. The finished attachment members 44 are made by a process described in detail below. Bridge 10 includes right and left male support members 46 and 48 soldered to inlays in right and left abutment teeth 50 and 52, respectively. Each male member is a solid piece extending mesio-distally from its corresponding abutment tooth for about one-half the width of a pontic 54 to be mounted on the male member. The male member also extends occlusogingivally the entire height of the pontic. The male member is generally rectangular, and includes a planar top edge 56 extending between a pair of longitudinally spaced apart, upright first and second edges 58 and 60, respectively, which extend occluso-gingivally for the entire height of the pontic. First upright edge 58 is located remote from the corresponding abutment tooth of the male member, and second upright edge 60 is attached to the abutment tooth. Top edge 56 traverses a major portion of the width of the male member, and a narrow, relatively shallow notch 62 is located in a minor portion of top edge 56. The depth of notch 62 extends for a relatively minor portion of the height of the male member so that a substantial amount of material provided by the solid male member can provide good means of support below the notch for the pontic to be releasably engaged with the male member. Preferably, the depth of the notch extends only about to 30% of the maximum height.

Each notch 62 preferably is located near the top corner of the male member adjacent the corresponding abutment tooth. The purpose of this preferred construction will be described in greater detail below.

. longitudinally extending, elongated bridge member 70.

Female members 66 and 68 are embedded in corresponding artificial teeth or pontics 54, and each is in the form of a socket adapted to be releasably engagedwith respective male members 46 and 48.

Each female member preferably includes an upright,

facial wall surface 72 spaced facio-lingually from an upright lingual wall surface 74. An end wall 76 at the remote end of the member from the abutment tooth connects surfaces 72 and 74. Lingual surface 74 includes an outwardly projecting right-angle channel 78 shaped to match the contour of shoulder 64 of the male member.

Surfaces 72 and 74 and end wall 76 extend the full height of the female member to form a socket adapted to make a snug, releasable'fit over the male support member. A transverse right-angle bridge piece 80 interconnects the top corners of facial and lingual surfaces 72 and 74 at the end of the female member adjacent the abutment tooth. Bridge piece 80 is shaped to fit the contour of notch 62.

In use, when either female member is mounted on its corresponding male member (only male member 46 and female member 66 are illustrated in FIGS. 3, 4 and 5), bridge piece 80 seats in notch 62 to provide an occlusal stop preventing further gingival movement of the female mem ber relative to the male member. Shoulder 64 interlocks with channel 78 when the two members are engaged to provide additional stability for the bridge, and to keep the pontics from drifting mesiodistally. 7

Bridge 44 provides substantial advantages over the prior art bridge shown in FIG. 1. Male member 46 is a substantially solid piece which eliminates the narrow.

leg 26, slot 30, and bridge portion 42 of the prior art male member. This substantially eliminates the chances of breakage, and also makes it much easier to fabricate the male member when compared with the prior art bridge. Further, the interlocking notch 62 and bridge piece 80 preferably are located adjacent the natural tooth support. This minimizes the leverage exerted at the point of contact between the two members during use, and thereby reduces the chance that breakage will occur during the life of the attachment.

A further advantage of bridge 44 is that the male and female members can be fitted into a shorter space mesio-distally than is possible with the prior art bridge shown in FIG. 1. Generally speaking, two male members and two cooperating female members are used in a bridge, whether the bridge includes one or more artificial teeth. Since leg 26 of each prior art male member chances of breakage, the ability of the prior art bridge to fit into narrow spaces occupied by a single artifical tooth is substantially limited.The present bridge eliminates this requirement, and a space as narrow as 7 mm.

can be fitted with a two-part bridge attachment 44.

' In the removable bridge attachment shown in FIG. 4, a vertically disposed narrow tension bar 82 is disposed between the lingual surface of shoulder 64 and the inner surface of channel 78. An exterior bottom portion 84 of the tension bar is bent back on itself adjacent the outer surface of channel 78. The bar is bent slightly by a mandrel (not shown) inserted in the interior of the female member so the bar applies tension between the cooperating male and female members and produces a tight releasable fit between the two members. The space left at the bottom of the tension bar is filled with self-curing acrylic resin-plastic, and the tension bar is held in place by such self-curing plastic around the bent end of the bar. The self-curing plastic is easily removable in the event the tension bar needs replacement.

The tension bar compensates for wear between the cooperating surfaces of the male and female members. If the tension on the bar needs to be increased due to wear, the female member simply is removed, and the mandrel inserted into the female member to bend the tension bar sufficiently to increase its tension.

FIG. 5 shows an alternate configuration of the attachment in which a tension bar 85 is disposed between second edge 58 of the male member and the interior surface of end wall 76 of the female member.

Referring to FIG. 6, attachment members 44 are made by starting with a solid male die member 86, and a socket-shaped female die member 87, both of which are made of a material which can be easily trimmed down to the shape of the finished male and female mounting members 46 and 66, respectively. Preferably, the male and female die members are made of plastic, rather than metal, such as gold, thereby facilitating ease of trimming the members and preventing waste of expensive material. However, the die members can be made of metal, if so desired.

FIG. 6 shows the male and female die members in their initial condition a they are sold to the dentist in preparation for his making the attachments. The male and female die members are the same width and thickness as the finished male support member 46 and finished female mounting member 66, respectively. The male die member includes a shoulder the same size as shoulder 58, and the female member includes a channel the same size as channel 78. The top corner of the male die member does not include notch 62, and the top corner of the female die member does not include bridge piece 80, because the notch and bridge piece will be added later by the dentist after the occlusal surfaces of the male and female die members have been ground to occlusion with the teeth of the opposite jaw.

'The finished bridge attachments usually are mounted with the shoulder 58 and channel 78 projecting toward the lingual side of the patients mouth. One advantage of die members 86 and 87 is their ability to serve as dies for either the right or left side of the bridge attachment simply by placing them right-side-up, or by inverting them, so that the shoulder and channel are kept on the lingual side.

The first step in forming the bridge attachments is to construct a stone model of the patients upper and lower jaws from impressions thereof so that the proper size and orientation of the attachment members can be obtained.

The female die members are mounted between the abutment teeth on the stone model, and mandrels (not shown) are then used for paralleling the female die members. A longitudinally extending body of selfcuring plastic material is then formed between the adjacent edges of the two female die members to form a bar, such as bridge member 70 shown in FIG. 2, for attaching the two female die members to hold them in their paralleled position. The female die members are then trimmed down to form dies having the shape which properly fits the patients bite as determined from the stone model. Notches 88 (shown in phantom line in FIG. are then cut in the corner of each female die member to serve as means for later adding occlusal stop 80 to the bridge attachment.

The resulting female dies are then removed from the stone model, and male die members 86 are ground gingivally and occlusally to match the contour of the previously ground female dies. A separate notch 89 (shown in phantom line in FIG. 5) is also cut in the top corner of each male die to match the notch of the cooperating female die.

The male die is then used to form a mold for casting the finished male support member 46 from metal such as gold. The cast male members are soldered to their respective abutment restorations, and are automati-.

cally paralleled with the aid of the female dies. If the indirect method of casting abutment restoration is preferred, male dies 46 can be cast with the restorations, eliminating soldering.

The female dies are fitted over their respective cast male support members. (In the original forming of each female die, a groove is provided between the male and female dies to accommodate the tension bar.) A body of self-curing plastic is then added to the notched portions of the male member and the female die to inter connect the opposite sides of the female die and form the die for bridge piece 80. The remainder of the desired occlusal surface of the pontic also is added in plastic or wax. The female dies are then removed from the male supportmembers, and are used to form a mold for casting the finished female mounting members which are then secured to pontics 54.

One advantage of this method of making the bridge attachments is that the original die members can be supplied in plastic patterns enabling the dentist or technician to cast his own attachments in any desired metal. This provides a saving of time and materials, because the preparatory work is done in plastics and wax. On the other hand, my previous bridge attachments shown in FIG. 1 cannot easily be manufactured by this method, primarily because leg 26 of the male member is too narrow, and therefore is difficult to cast without being so brittle that it will break easily. To avoid breakage of the male members, they would have to be cast in such large pieces that they are virtually of little practical use for most patients.

FIGS. 7 and 8 schematically illustrate a removable bridge attachment 90 especially designed to mount a single artificial tooth. The attachment includes right and left male members 91 and 92 identical in construction to male support members 46 and 48. Male members 91 and 92 are secured to inlays (not shown) in adjacent natural tooth abutments (not shown) in a manner identical to male support members 46 and 48.

Bridge also includes a pre-paralleled double female mounting member 94 to be embedded in a single pontic (not shown) and adapted to releasably fit over the two male members to hold the pontic in place. The double female member includes an elongated upright facial surface 96 adapted to abut against the facial surfaces of the male members, and a lingual surface 98 spaced facio-lingually from the facial surface 96 and adapted to abut against the lingual surfaces of the male members. Lingual and facial surfaces 96 and 98 are parallel to each other and extend mesio-distally for a major portion of the width of the pontic. An outwardly projecting channel 100 is formed in the intermediate portion of lingual surface 98 to accommodate both lingual shoulders of the two male members. An internal transverse center wall 102 divides the female member in half. The top right and left corners of the double female member also include transverse bridge pieces 104 and 106, respectively, adapted to seat in the corner notches of the two male members.

A U-shaped tension bar 108 applies tension to the cooperating male and female members of bridge 90. The tension applying legs of tension bar 108 are disposed between the proximal ends of the two male members and the opposed surfaces of center wall 102.

FIG. 8 shows an alternate bridge attachment 110 which is similar to bridge 90, except that tension bar 108 is replaced by a pair of side-by-side right and left tension bars 112 and 114 on the lingual side of the attachment. In bridge attachment 110, the lower exterior portions of the tension bars are bent back, as described above for tension bar 82, to apply tension in compen sating for wear between the bridge members.

Bridge attachment 88 occupies less space faciolingually than bridge 110, because U-shaped tension bar 102 is located completely internally in the attachment. Accordingly, bridge 90 is used in instances where a tooth is so narrow that there is insufficient space to accommodate the bent back portions of the tension bars in attachment 110.

Thus, the removable bridge 44 has improved strength, and the ability to resist breakage when compared with known prior art removable dental bridges. Moreover, the bridge 44 is simple in configuration, which reduces fabrication time and costs.

FIGS. 10 through 13 show a patient-removable dental bridge 118 which is an alternate embodiment of this invention. The bridge 118 includes right and left male support members 120 and 122, respectively, soldered to or cast with inlays in right and left abutment teeth 124 and 126, respectively. Each male support member is identical in construction to male support members 46 and 48 described'above, the male support members including respective notches 128 and 130 located adjacent their respective abutment teeth. The male support members also include respective right- angle shoulders 132 and 134 projecting inwardly along the lingual side of the bridge attachment.

The bridge 118 also includes a female bridge attachment which comprises right and left socket members 136 and 138, respectively, and an occlusal cap 140 adapted to be attached to the tops of the two socket members. The socket members are similar in purpose to the female mounting members 66 and 68 described above in that they provide corresponding L-shaped sockets 142 which slidably fit over their corresponding male support members.

Occlusal cap 140 comprises a pair of interconnected right and left top pieces 144 and 146 which provide occlusal surfaces cast to simulate the contour of the natural teeth. Each top piece of the occlusal cap includes opposite lingual and facial extensions 148 and 150 which abut against opposite lingual and facial surfaces 153 and 154, respectively, of their corresponding female socket members when the occlusal cap is attached to the top of the socket members.

The method for making right and left pontics 156 and 157 from the female socket members and the occlusal cap is as follows. Male and female plastic die members as described above are initially trimmed down to their desired size and shape. The properly-shaped plastic female die members serve as the female socket members 136 and 137 and are incorporated into the final pontics 156 and 157, rather than casting the female socket members out of metal. After the male and female die members are properly positioned with respect to each other, the properly-shaped male die members are then used to cast the male support members 120 and 122 in metal such as chrome or gold. The cast male members are then soldered to or cast with respective abutment teeth 124 and 126.

The occlusal cap 140 is then cast from any desired metal. Because of the recently increasing cost of precious metals such as gold, it is preferred to cast the occlusal cap from a chromium alloy. The occlusal cap is cast around the attached male and female members so that the facial and lingual extensions 148 and 150 of the occlusal cap make a tight sliding fit against the facial and lingual surfaces 152 and 154 of the socket members. The occlusal cap also is cast to include a pair of mesio-distally spaced apart, L-shaped central openings 158 and 160 which receive the top portions of the male support members 120 and 122 when the occlusal cap and the female socket members 136 and 138 are mounted on the male support members.

The continuous end portions 162 and 164 of the occlusal cap are cast so they fit snugly into the respective notches 128 and 130 of the male support members to provide corresponding bridge pieces which provide an occlusal stop preventing further gingival movement of the artificial teeth 156 and 157 relative to the male support members. Shoulders 132 and 134 of the male members also interlock with corresponding channels formed on the lingual side of the socket members 136 and 138 to provide additional stability for the bridge and to keep the artificial teeth 156 and 157 from drifting mesio-distally.

The artificial teeth 156 and 157 are completed by forming the balance of the teeth in a plastic material such as acrylic. The acrylic material provides means for bonding the occlusal cap 140 to the female socket members 136 and 138 so that removable artificial teeth 156 and 157 are an integral unit. Moreover, the lingual and facial extensions 148 and 150 of the occlusal cap become embedded in the acrylic to provide lingual and facial reinforcement for the artificial teeth. Alternately, extensions 148 and 150 can be cast as pins rather than flange-like members, although the flange-like embodiment shown in the drawing is preferred because of the added reinforcement they provide.

As a final step, appropriate tension bars (not shown because of clarity), such as those described above, are

inserted between the facial socket members and the male support members.

I claim: 1. A patient-removable dental bridge system for re- 5 movably mounting a pontic, the system comprising a male supporting member affixed to an abutment tooth to serve as a bridge support, the male member being a solid piece extending mesio-distally from the abutment tooth for about one-half the width of the pontic, the male member having a pair of spaced apart, upright first and second edges which extend occlusogingivally for a major portion of the height of the pontic, and a top edge extending mesio-distally between the first and second edges of the male memher, the top edge having a first portion extending from the first upright edge toward the: second upright edge and traversing a major portion of the width of the male member, and a second. portion which is recessed to form a relatively shallow notch in the top edge of the male member adjacent the abutment tooth, the depth of the notch extending for a minor portion of the height of the male member, and female member rigidly secured to the pontic, the female member comprising a socket member shaped to be releasably mounted on the male member, the socket member providing spaced apart lingual and facial surfaces to be releasably engaged clusal cap shaped to be fitted on the top of the socket member, the occlusal cap including a bridge piece shaped to match the size and shape of the notch in the male member, the bridge piece being positioned relative to the male member to make a tight fit in the notch of the male member when the female member is mounted on the male member so the bridge piece and notch cooperate to prevent relative movement mesio-distally and occlusogingivally between the pontic and the male memher.

2. Apparatus according to claim 1 in which the first upright edge is spaced remote from the abutment tooth and extends the entire height of the male member, the second upright edge is adjacent the abutment tooth and extends upwardly from the gum tissue for a major portion of the height of the male member, and the first portion of the top edge intersects the first upright edge and portion of the width of the member, said notch being formed by the second portion of the top edge at the upper corner of the male member adjacent the abutment tooth.

3. Apparatus according to claim 1 including a shoulder continuous with the first upright edge of the male member, and in which one of the said surfaces of the female members includes a channel projecting away from the opposite surface thereof to match the contour of the shoulder of the male member so the channel can be releasably fitted over the shoulder to interlock the male and female members.

4. Apparatus according to claim 1 including a tension bar between the male member and the socket member.

5. Apparatus according to claim 1 in which the socket member includes a lingual wall having an outer surface spaced from said lingual surface, and a facial wall having an outer surface spaced from said facial with opposite sides of the male member, and an ocextends toward the second upright edge for a major male member projects into the central opening of the occlusal cap to make a tight, releasable fit therein.

8. Apparatus according to claim 1 in which the occlusal cap is cast in metal.

9. Apparatus according to claim 8 in which the occlusal cap is made of chrome.

10. Apparatus according to claim 8 in which the socket member is made of plastic.

Claims (10)

1. A patient-removable dental bridge system for removably mounting a pontic, the system comprising a male supporting member affixed to an abutment tooth to serve as a bridge support, the male member being a solid piece extending mesio-distally from the abutment tooth for about one-half the width of the pontic, the male member having a pair of spaced apart, upright first and second edges which extend occluso-gingivally for a major portion of the height of the pontic, and a top edge extending mesio-distally between the first and second edges of the male member, the top edge having a first portion extending from the first upright edge toward the second upright edge and traversing a major portion of the width of the male member, and a second portion which is recessed to form a relatively shallow notch in the top edge of the male member adjacent the abutment tooth, the depth of the notch extending for a minor portion of the height of the male member, and a female member rigidly secured to the pontic, the female member comprising a socket member shaped to be releasably mounted on the male member, the socket member providing spaced apart lingual and facial surfaces to be releasably engaged with opposite sides of the male member, and an occlusal cap shaped to be fitted on the top of the socket member, the occlusal cap including a bridge piece shaped to match the size and shape of the notch in the male member, the bridge piece being positioned relative to the male member to make a tight fit in the notch of the male member when the female member is mounted on the male member so the bridge piece and notch cooperate to prevent relative movement mesio-distally and occluso-gingivally between the pontic and the male member.

2. Apparatus according to claim 1 in which the first upright edge is spaced remote from the abutment tooth and extends the entire height of the male member, the second upright edge is adjacent the abutment tooth and extends upwardly from the gum tissue for a major portion of the height of the male member, and the first portion of the top edge intersects the first upright edge and extends toward the second upright edge for a major portion of the width of the member, said notch being formed by the second portion of the top edge at the upper corner of the male member adjacent the abutment tooth.

3. Apparatus according to claim 1 including a shoulder continuous with the first upright edge of the male member, and in which one of the said surfaces of the female members includes a channel projecting away from the opposite surface thereof to match the contour of the shoulder of the male member so the channel can be releasably fitted over the shoulder to interlock the male and female members.

4. Apparatus according to claim 1 including a tension bar between the male member and the socket member.

5. Apparatus according to claim 1 in which the socket member includes a lingual wall having an outer surface spaced from said lingual surface, and a facial wall having an outer surface spaced from said facial surface, and in which the occlusal cap includes a lingual extension for abutting the outer surface of the lingual wall and a facial extension for abutting the outer surface of the facial wall.

6. Apparatus according to claim 5 in which the pontic includes a bonding material for rigidly securing the occlusal cap to the socket member.

7. Apparatus according to claim 5 in which the occlusal cap includes a central opening shaped to the contour of the male member, and in which the top of the male member projEcts into the central opening of the occlusal cap to make a tight, releasable fit therein.

8. Apparatus according to claim 1 in which the occlusal cap is cast in metal.

9. Apparatus according to claim 8 in which the occlusal cap is made of chrome.

10. Apparatus according to claim 8 in which the socket member is made of plastic.

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