GB109651A - Improvements in or relating to Artificial Teeth. - Google Patents

Abstract

109,651. Earp, S. Sept. 20, 1916. 'I'eeth, artificial. - Full-contour all-porcelain tooth crowns A for use with vulcanite dentures are formed with a hollowed interior surface tapering outwards from within the incisal edge of the base, to receive the filling C of vulcanite within which is embedded a post B, of suitable metal, secured to the tooth at the apex of the hollow within the incisal edge and extending the full depth of the tooth. The post is secured at its point either by being fired in or by being soldered to a capsule F of platinum, preferably split and previously fixed to the crown, and in the form either of a narrow ring, or extending the whole distance of the interior, Fig. 3, in which case it may have a spiral rib H engaging a corresponding groove on the interior surface of the porcelain. Alternatively, the post is fixed by means of Brills' cement or other material unaffected by vulcanization; it is of any usual form, splayed, headed, hooked, or provided with projections to give a greater surface of engagement for the vulcanite. In the absence of a deep capsule, the interior of the cavity is formed with a spiral groove or serrations E in order to key the vulcanite securely thereto; the post is provided also with inclined stepwise surfaces G to prevent the tooth from being pulled off; and pins, tags, or flanges on the interior of the tooth may additionally secure the vulcanite. Laterally extending passages D give relief to the pressure caused by expansion during vulcanization, and there may be a thickening I over triangular areas at the sides to preserve the natural appearance, more particularly in the case of lower central and upper lateral incisors.