US2721387A - Artificial tooth - Google Patents

Description

Oct. 25, 1955 E. s. ASHUCKIAN 2,721,387

ARTIFICIAL TOOTH Filed July 13, 1953 lai- INVENTOR fbAW/RD 5 /4S//(/C/f//1/I/ BY MW TO RN EYS United States Patent ARTIFICIAL TOOTH Edward S. Aslluckian, Alameda, Calif.

Application July 13, 1953, Serial No. 367,457

3 Claims. v(Cl. 3210) The present invention relates to artificial teeth and in more particular to one which is adapted to be inserted in the socket of a tooth which has just been extracted so as to take the place of the extracted tooth, and to be retained in the position of the extracted tooth without bridging or other support from the proximal or other teeth in the denture. A further aspect of this invention is the process of establishing an artificial tooth in the alveolar process of a jaw.

There have been attempts to provide a substitute tooth which would fit in a socket but such efiorts have not been satisfactory because the replacement has not been nor become integrated in the bone structure of the jaw. If the substitute is not firmly in place, it willmove and work in the socket, enlarge and irritate the surrounding structure, and generally prove unsatisfactory.

Having in mind these defects of the prior art, it is an object of the present invention to devise an artificial tooth which may be firmly anchored in a tooth socket.

A further object of the present invention is the performance of a process of placing an artificial tooth in a tooth socket.

Another object of the present invention is the devising of a tooth root which after placing in a socket may be expanded to anchor it in place.

A still further object of the present invention is the construction of an artificial tooth root which when inserted in a tooth socket lends itself to ready, rapid, and firm integration with the surrounding structure.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawing accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawing and description may be adopted within the scope of the invention as set forth in the claims.

The above mentioned defects of the prior devices intended as inserts in the alveolar process in place of extracted teeth are remedied and these objects attained by the construction of an artificial tooth having one or more roots, as may be desired, which after insertion in a tooth socket immediately after extraction of the natural tooth therefrom are expandable transversely of the axis of the root so as to firmly engage the walls of the socket. .The outer surfaces of the inserted root are roughened to form outward projections and the walls formed with either deep depressions therein or holes therethrough so that immediately upon installation, expansion of the root will firmly establish the artificial tooth to preventsuch movements as would make impossible integration in the alveolar process while during healing the surrounding structure fills in these openings in the artificial tooth root to accomplish integration.

Five variations constructed in accordance with the above outline are hereinafterdescrbiedin detail, and.

Patented Oct. 25, 1955 ice these modifications are shown in the accompanying drawing, in which:

Figure l is a lingual elevational view of an artificial tooth embodying the present invention with parts of a surrounding socket as it would appear at the time of insertion of such tooth.

Figure 2 is an elevational section taken on the line, 22 of Figure 1.

Figure 3 is a transverse sectional view taken on the line 33 of Figure 2.

Figure 4 is an elevational view in full of the tooth root shown in Figures 1, 2, and 3.

Figure 5 is an elevational view of a tooth root having two branches, each of which is similar to the root shown in Figures 1 to 4, inclusive.

Figure 6 is an elevational section of the root shown in Figure 5, with a crown added thereto, and the tooth in place in an alveolar process, also, shown in section.

Figure 7 is a transverse elevational view through an illustrative alveolar process and tooth socket in which there has been recently installed an artificial tooth embodying another form of my invention.

Figure 8 is an elevational view, partly in section, of a tooth root embodying another form of the invention.

Figure 9 is a view in elevational section embodying a further modification of the invention of an artificial tooth root.

Figure 10 is a transverse sectional view on the line 1010 of Figure 9.

The particular embodiment of the invention shown in Figure 1 has as the principal parts of the tooth a crown 11 having therein a recess 12 adapted to receive a pin 13 which is integral with the root portion of the tooth. The pin is secured in the recess by a suitable cement. The view of Figure l is of the lingual surface of an incisor tooth, and so there is only one root portion, no branches. The root has a neck 14 that fills the entrance to the socket in the alveolar process 19 of the jaw. The gum, or gingiva, 20 covers the alveolar process and meets the neck of the crown 11 exteriorly of the neck 14 of the root. The root and the crown being joined adjacent the gingival surface.

Extending from the neck 14 of the root is the main part of the root which lies deep in the socket and is in the form of a V with a fixed leg 21 joined to the neck 14, the apex 22 of the V adjacent the bottom, or remote part, of the socket, and the free leg 23 of the V more or less parallel to the fixed leg 21. Each of the legs is formed with a thin wall shaped and rounded so that the two legs of the V are part of a hollow cone, shaped so that the outer surface conforms to the inner surface of the tooth socket. The outer surfaces of the root parts are roughened as by shearing and striking out small sections 24 of the walls of the root. Other openings 26 than those formed by the striking out of the sections 24 may be formed in the root walls. The purpose of these projections 24, or spurs, and openings 26 is to aid in firmly anchoring the artificial roots in the natural socket. When first inserted in the socket, the struck out sections 24 serve to firmly hold the tooth in place when the springy nature of the material and construction of the tooth root expand the legs 21, 23 away from each other and against the walls of the socket when inserted therein. Also, the spurs aid in retaining the root in the socket without crowding or damage to the lamina dura or other existing structure. The healing process will fill in the holes in the roots with tissue and eventually all of the unused parts of the socket to firmly anchor the tooth in place. Prior to extraction of the old tooth which the artificial one is to replace, X-rays of the old tooth should be taken to determine the shape and location of the root systemso that a properly shaped artificial tooth is at hand to replace the old one when it is extracted. A small amount of shaping of the root may be done by bending and trimming thereof, as by the removal of some of the V point 22 and edges of the legs 21, 23.

Figure 4 is an elevational full view of only the root of the tooth shown in the previous figures.

Using this structure and this process, there will be substituted for a natural tooth an artificial one that will be comfortable to the person and will in some respects be superior to the natural tooth. Further, it will be an artificial tooth which does not depend upon the proximal, adjacent teeth for support and retention, nor does the artificial tooth impose a load upon the adjacent teeth which tends to weaken them in their sockets.

Figures 5 and 6 show a modification of the previously described structure in which there are two branches of the root integral with a single neck for insertion in the socket of one of the back teeth. While only two branches are shown, it is obvious that three branches could be provided for replacement of those teeth having three branches to the root.

Figure 6 shows the complete tooth in place in the alveolar process 19 with the gingiva 2th contacting the neck of the crown 31 which is formed with a recess 32 to receive a pin 33 integral with the neck 34 of the root portion of the tooth. This neck 34 of the root has secured to and integral therewith two fixed legs 36, 37 which with the free legs 38, 39 form two Vs, each of which is inserted in a corresponding branch of a socket. These legs are formed with struck out projections 42 and holes 43 as in the preivously described form, as each branch is similar in form and construction to the single root branch of the previously described form.

Figure 7 shows a form of the invention adapted for a socket having a plurality of branches and is which at the time of insertion of the artificial branches there is no portion common to the branches. The modification of this figure has as its principal parts a crown portion 51 shown in elevational section to disclose the recesses 52 in its gingival surface in each of which is placed the head part 53 of a root branch portion of the tooth. In this modification each branch is V-shaped in form, one leg 54 having at its free end the head 53 to which the crown 51 is secured by suitable means such as a cement 56. The other, or free, leg 57 of the branch is free to move as it is joined to the head leg 54 only at the apex of the V. This root or branch may be constructed out of round wire or narrow strip and is of a cross sectional area that will allow the root when formed to be easily inserted in a tooth socket. The material used should have some resiliency so that the free ends of the V may be drawn together for easy insertion in the tooth socket, and so that after insertion the ends of the V may be released and the two legs will separate, or expand, under their spring action to press against the sides of the socket and root opening. The surface of the inserted root legs 54, 57 is roughened so that it will have projections 58 which will engage the lamina dura and the bone structure 19 of the alveolar process which surrounds and forms the tooth socket but will allow the healing growth of tissue around the root inserts.

The artificial root, roots, or branches are inserted in the socket upon extraction of the natural tooth and the healing processes will soon fill in the remaining opening of the socket and more firmly anchor the roots in place. This anchoring is facilitated by the roughness and irregularity of the inserted material and by the tapering shape of the V of the root and the transverse opening between the legs 54, 57 thereof. The outward expansion of each root branch embeds the projections in the lamina dura and holds the root firmly in place during the healing process so that there is no movement of the root which would prevent proper healing and integration of the root with the surrounding material.

The crown S1 of the tooth may be added after the healing process has been well advanced or completed. The process of adding such crown may be the same as that used in the application of a crown to the neck of a natural tooth, the taking of an impression to locate the positions of the heads 53 of the roots and the shaping of the crown with regards to the gums 20, or gingival tissues, and the type of tooth being replaced, and the cementing of the crown in place on the heads of the roots.

Other forms of the invention are shown in Figures 8, 9 and 10 wherein the alveolar process and gingiva forming the tooth socket would be similar to that shown in Figures 5 and 1, respectively. Also, as in the previous forms, a crown portion having a recess in its gingival surface is secured by cement to the upper, or neck, end of one or more artificial roots.

The modification shown in Figure 8 has a pin 63 adapted to fit in a recess in a crown which will then contact the gingival surface of the neck 64 of the root. Secured across the neck portion from the pin 63 are two root branches 66, 67 which are thin walled, outwardly convex, and taper from the neck portion to the tip of each root. When the roots are inserted in a socket, the form and springiness of the material will cause the roots to press outwardly of each other and against the walls of the socket to hold the roots and the tooth firmly in position. The holding power of the roots is increased by the outwardly struck projections 68 distributed over the outer surfaces of the roots, which projections will embed in the socket walls. Openings 69 in the root walls aid in the integration of the roots with the alveolar process during the healing of the socket.

The root portion shown in elevational section in Figure 9 has only one branch. The pin 73 which is adapted to be secured in a recess in the gingival surface of a crown, and the neck 74 of the root are provided with an opening 76 extending therethrough longitudinally and having placed therein a screw threaded stem '77 with a head 78 secured to an end projecting above the free end of the pin 73 so that the underside of the head rests on the free end of the pin 73. The screw threads of the stem 77 co-operate with a transversely elongated nut 78 that has its narrower ends 79, 80 guided in slots 81, 82 in the opposed longitudinal parts 83, 84, or legs, formed by the bifurcation of a portion of the root. The slots 81, 82 and the opposed parts 83, 84 are so formed that the slots diverge from the neck 74 to the tip of the root, and the placing of portions 79, 80 of the nut 78 in the slots 81, 82 prevents turning of the nut with the stem and forces apart the legs 83, 84 of the root when the nut is moved toward the neck of the root.

Figure 10 shows the sectional form of the legs 83, 84. The legs are formed with outward projections 86 and openings 87 similar to those found in the other modifications, and used for the same purposes. The spurs 86 not only project into the lamina dura to anchor the tooth root when first inserted in a socket, but they serve to space the greater part of the root from the walls of the socket.

This construction, illustrated in Figures 9 and 10, provides positive means for expanding a root so that it will be held in a tooth cavity.

The root portions of these artificial teeth may be constructed of tantalum, chrome cobalt iron alloy, or other suitable material which is tolerant to the tissues which it will contact. The crowns may be made of porcelain, or suitable plastic material.

What is claimed is:

1. An artificial tooth comprising a root portion and a crown portion, means for securing said root portion to said crown portion, said root portion being formed as a generally bifurcated member with an apex thereof being downwardly directed, said member being formed of resilient material whereby the bifurcations of said member may be urged inwardly towards each other, and

said member being provided with a plurality of projections extending from the surface thereof.

2. An artificial tooth comprising a root portion and a crown portion arranged to be secured together, said root portion having a substantially solid portion adjacent said crown and a pair of generally parallel spaced elements extending downwardly therefrom, each of said elements being provided with an oppositely disposed loop portion with the distal ends thereof directed towards said crown,

and said loop portions and said elements being movable 10 relative to each other in planes generally normal to the longitudinal axis of said tooth.

3. An artificial tooth as set forth in claim 1 in which a plurality of perforations are provided in said member 5 extending to the outer surface thereof.

References Cited in the file of this patent FOREIGN PATENTS 617,412 France Nov. 20, 1926

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