Artificial tooth-crown.

(Application filed July 20, 1901.) (No Model.)

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• THE NORRIS PETERS CiT. PHOTO-LITHO.. WASHINGTON. 0. C.

United States Patent Office.

JOSEPH 0. OSBORNE, OF LAWNDALE, NORTH CAROLINA.

ARTIFICIAL TOOTH-CROWN.

SPECIFICATION forming part of tetters Patent No. 702,111, dated June 10, 1902.

Application filed July 20,1901. Serial No. 69,076. (No model.)

To all whom It may concern:

Be it known that I, Joseph 0. Osborne, a citizen of the United States, residing at Lawndale, in the county of Cleveland and State of 5 North Carolina, have invented a new and useful Artificial Tooth-Crown, of which the following is a specification.

My present invention relates to a novel artificial tooth-crown; and my object is to proro vide the crown with an improved post for effecting its mounting upon a natural root with convenience and expedition and in a manner to insure the rigid retention of the crown in place.

A further object of the invention is to so form the pivot-pin or crown-post as to preclude the possibility of the displacement of the crown in either a longitudinal or a lateral direction with respect to the post, and to so 20 dispose the post as to present its greatest diameters from mesial to distal and from palatal to labial, so that the post will be capable of presenting the greatest resistance in those directions from which it is subjected to the 25 greatest strains.

In the accompanying drawings, in which I have illustrated the application of my invention, Figure 1 is an elevation of a crown mounted in accordance with my invention.

Fig. 2 is a sectional view of the subject-matter of Fig. 1. Fig. 3 is a similar view taken at right angles to Figi 2. Figs. 4, 5, and 6 are transverse sectional views on the lines 4 4, 5 5, and 6 6 of Fig. 2. Fig. 7 is a longi35 tudinal sectional view of the crown detached, and Fig. 8 is a detail view of the crown-post detached.

Like numerals of reference refer to corresponding parts and structural peculiarities 40 throughout the views.

The natural root 1 and the artificial crown 2 are provided, as usual, with longitudinal recesses or cavities 3 and 4 for the reception of the opposite end portions of the crown-post 0.

In this general aspect my invention is allied to the usual forms of mountings for artificial tooth-crowns; but it is distinguished from the usual constructions by the relative formations of the cavities 3 and 4 in the root and 50 crown and by the corresponding contours of those portions of the post which engage the cavities to effect the mounting of the crown.

The root-engaging end of the post 5 is provided with screw-threads, as indicated at 6, and is designed to be screwed into the cylin- 55 drical socket, channel, or cavity 3 of the root, while the crown-engaging portion 7 of the post instead of having a flat or cylindrical form, as in ordinary mountings, is square in cross-section for engagement with the corre- 60 spondingly-shaped cavity 4 of the crown.

One of the distinguishing characteristics of the invention will now be apparent, since by reference to Fig. 5 it will be noted that the post is so disposed within the crown 2 as to bring the 65 greatest diameters of said post between the . mesial and distal and the palatal and labial _?sides, respectively, of the crown—that is to say, the square portion of the post has its several angles disposed opposite the mesial,distal, 70 palatal, and labial sides of the tooth, so that said post will present the greatest resistance in those directions from which the crown is subjected to the greatest lateral strains. It will also be observed that this angular contour of 75 the post will absolutely prevent the turning of the crown thereon, and in order to prevent the longitudinal displacement of the crown I provide the post adjacent to one extremity with a reduced portion or neck 8, defining a 80 terminal head 9, which bears against the end of the cavity 4 in the crown. Opposite this reduced portion or neck of the crown-post 5 the lingual or palatal face of the tooth is pierced by a transverse opening or recess 10, 85 intersecting the cavity 4 at the end thereof and designed to facilitate the introduction of an alloy or other filling 11. This filling, which may be quickly and conveniently inserted, extends around the neck 8 of the post, 90 completely filling the annular cavity there formed, and extends into the transverse opening or recess 10 to constitute a key, which prevents the slightest longitudinal movement of the crown upon the post. The filling, hav- 95 ing been properly inserted, is finished off flush with the surface of the tooth and the crown will be securely retained in place upon the root.

Obviously the order of procedure in effect- 100 ing the mounting of the crown in accordance with my invention is not essential, since the crown may be secured upon a post previously set into the root, or the reverse of this pro702,111 cedure may be adopted. It is likewise immaterial what metal is adopted in the manufacture of the post or what material is selected for the filling. Therefore I desire to 5 be understood as reserving to myself the right to effect any changes, modifications, or variations of the illustrated construction and arrangement which may appear to be expedientundervariousconditions, provided only io that such variations are fairly comprehended within the scope of the protection prayed.