US2370488A - Artificial tooth - Google Patents

Description

- Feb. 27, 1945. w. D. RABER 2,370,488

ARTIFICIAL TOOTH Filed March 8, 1943 Patented Feb. 27, 1945 UNITED STATES QFFICE I a I r 2,370,488"

ARTIEIGI-ALJIEQQIIJH. WaIter D. Raber, Chicago, Ill; 7 Application March 8. 194a seam. grant .(o1; sz-s) 2* Claims.

This inuention relates to iiriproveinents;v in, artificial teeth; and more: particularly to a tooth hatmesnoyel meanaofJretentiOn. One obj ct is taprorLi-de as diatoriotooth of i strength and beauty and atooth that; really. presents: the ppearance of anatural tooth. .Heretoiore pinless. or die.- torieteeth havezbeenr; lacking instreneth atjvital points,- notably attire denture.- basewith. theirs..- suit-j. that. breakages; are,- of." frequent occurrence. Thishas been, due; to faulty: retention; the; re .tention being; placedwholly or; mainlyin; the gingiual. part at. the tooth, resulting; in; such ex;- treme leverage that: pressure; applied. elsewhere upon the tooth must result in breakage: at: the point-on entry ofretention into the base of the tooth.

A further object, therefore, of the instant invention is to provide retention extending well into the incisal half of the tooth so that it is efliciently supported throughout the major portion of its area or extent with the result that a maximum amound of grinding at the gingival or cervical end is readily possible without in any way less-' ening the retention efficiency and in this manner the formerly long present long leverage from any point of external tooth pressure to a point of retention is greatly reduced and breakage likewise curtailed or eliminated.

A further object of the instant invention is to provide an artificial tooth having a multi -point or finger-like interlocking of the tooth with the base material combined with a post of moderate diameter which therefore affords the strength of a much larger post than actually otherwise must be used. This specific structure provides a tooth well adapted for use as the end tooth of a partial denture because of the multi-point support at the base of the post. This great supportpost efficiency is highly important because most denture base materials in use today are of a brittle nature and become more brittle as the denture ages.

A still further object is to provide an artificial tooth of long lingual surface with the attendant obvious advantages, as well as a tooth having a wholly unobstructed exterior thus affording a long bite of maximum efllciency.

A still further object is to provide an artificial tooth of great strength at all points and one that due to its specific retention is adapted for use at any and all points of the denture, one that adapts itself to overlapping as well as to positioning at any desired angle to the eases. desired interfitting is. possible without weakening at: any point;.

With the foregoing: and" other objects. in view the; invention consists in. the combination and arrangement-4dr" parts to. be hereinafter fully de-,

scribed; pointed; out in the claims and: illustrated in the accompanying drawing which formsv apart on thisnatentzandrwhich- .1 is a. view in side; elevation of" a tooth embodying the present invention illustrating: its

' applihation to thegum,.the;retention= post of:den;-

teeth adjoining and onewherein grinding to 65 'ture material filling: the, tooth: cavities; being Fig. 6 is a View similar to Fig. 5 but taken horizontally through Fig. 3.

Fig. 7 is a view similar to Fig. 6 but illustrating a slightly modified form of tooth, and,

Fig. 8 is a view in elevational perspective of the plastic core or post formed in the tooth cavities.

Like reference characters denote corresponding parts throughout the several views.

The reference numeral I denotes the tooth that is formed with a large cavity 2 opening on the gingival side and extending substantially centrally well into the incisal half of the tooth, the lower body portion 3 terminating in the cavity base 4. The mouth of the cavity 2 is enlarged by the opposed recesses 5, 6 extending therefrom to the lateral faces [3, I4 of the tooth substantially midway between the buccal or labial and lingual sides, and by a recess 1 extending from said mouth approxinfately midway between recesses 5, B lingually almost to that face, said recess 1 diminishing in depth as it recedes from said cavity mouth.

Diverging from each other are the opposed twin undercut cavities 8, 8 that register with the lower end of said cavity 2, said undercut cavities being of materially smaller diameter and extent than said cavity 2 and extending from said cavity toward opposite incisal points of the tooth.

Also registering with said cavity 2 are the opposed cavities 9, 9, said cavities 9, 9 being provided only in teeth of suflicient length to require or make desirable a precautionary support.

In use the tooth is applied to the rubber or other material of which the plate is made while the material is in a plastic or semi-liquid state so that the material will flow into the cavity 2, recesses 5, 6, 1 and cavities 9,9 and when hardened will form tooth retention engaging the tooth at many points. It will be noted that the recesses 5, 6, 1 form a three-prong tooth gripping and supporting means about the mouth of the cavity 2 while the diverging cavities 8, 8 form a wedgeshaped retention seated well in the incisal half of the tooth and cooperating with the major cavity and recesses to effectually resist breakage at the cervical end of the toothas well as providing resistance to twisting and distortion.

The major tooth cavities while of substantial size do not weaken the tooth structure as they are mainly disposed centrally and extend from the lap face II more than half the distance to the incisal edge afiording, when filled with den.-

ture material, the maximum degree of denture retention. Referring now to Fig. 7 only, the tooth is formed in this slightly modified form with oppositely disposed vertical recesses l0, 10a formed in the tooth surface approximately midway between the labial and lingual faces and retention.

In Fig. 8 the denture material received in the tooth cavities and recesses is shown apart from the tooth and comprises the post 15, the three fingers I6 and diverging prongs [1 which respectively occupy the cavity 2, recesses 5, 6, 1 and undercut cavities 8, 8.

I do not desire to limit my invention to the specific details of construction and arrangement'as herein set forth, and consequently wish said first named cavity and extending therefrom to opposite faces of the tooth and with a third recess communicating with said first named cavity disposed substantially at right angles to said opposed recesses, all of said cavities and recesses receiving the denture plate base material in which the tooth is mounted.

2. An artificial tooth having a cavity extending from the lap face in an incisal direction throughout the major portion of the tooth, the innermost end of said cavity being undercut to form .25 which recesse's also receive denture material for" smaller communicating cavities diverging from each other in the general direction of opposite terminal points of the incisal edge of the tooth. the lap face of the tooth being formed with two opposed recesses communicating with said first named cavity and with a thirdrecess communicating with said first named cavity disposed sub.-

, stantially at right angles to said opposed recesses,

said cavities and recesses receiving the base material of the denture plate in which the tooth is mounted. Y

WALTER D. RABER.

Images