US1172652A - Tooth-crown. - Google Patents

Description

T. H. WHlTESlDE.

TOOTH CROWN.

APPLICATION FILED MAR. 16. 1915.

Patented Feb. 22, 1916.

5140a 14 'fioz WW 7155/05.

a t-foam THOMAS H. WHI'IESIDE, or YOUNGSTOWN, onto. 7

TOOTH-CROWN.

Specification of Letters Patent.

"Application filed March 16, 1915; SerialNo. 14,704.'

To all whom it may concern:

Be it knownthat I, THOMAS H. WHITE- smn, a citizen of the United States, residing at Youngstown, in the county ofMahoning and State of Ohio, have invented certain new and useful Improvements in Tooth- Crowns, of which the following is a specification. i This invention relates to dentistry, and moreparticularly to a novel artificial tooth mounting of specialutility in the prepara' tion and fitting of. crowns.

. Primarily, the invention contemplates making the several parts of the mounting so that they can be expeditiously dressed of substantially uniform size and design,

and fitted to meet the requirements of each particular case. That is to say, the invention aims to substantially standardize a novel form of tooth crown which'will greatly facilitate; the application of the crown to the tooth root and also strengthen the rigid connection between the porcelain'facing and the metallic backing of the crown. Accordingly, to attain these ends the invention proposesto utilize a novel metallic backing in combination. with porcelain facings which are readily interchangeable, thus rendering it possibleto keep a wellassorted stock of facings on hand which may be easily adapted to the backing with very little grinding or dressing of the parts. 7 g

A further object of the invention is to 7 provide a simple and substantial construction whereby the full biting force imposed upon the working edge of the facing is not borne entirely by theelementswhich secure it to the backing. In other words, the invention makes provision for g the metallic backing to share the great part of the biting force, thus reducing the possibility of shearing off the related parts. 7

With the above and otherobjects in view which will more readily appear asthe nature of the invention is better understood, the same consists in the novel construction, combination and arrangement of parts hereinafter more fully described, illustrated and claimed' A preferred embodiment of the invention is shown in the accompanying drawings, wherein Figure 1 is a perspective view of a porcelain crown facing constructed in accordance with the present invention. Fig. 2 is an elevation of a complete tooth crown prior to assembling, andshowing the metalllc backing having a tooth-root post, thus adapting the invention to be applied to a natural tooth root. Fig. 3 is a sectional view showing the application of the invention to a natural tooth root. Fig. 4 is a perspective vlew showing the application of the invention to bridgework.

Similar reference characters designate cor: respondlng parts throughout the several.-

figures of the drawings.-

In carrying out the invention, it is pro- Patented Feb.22, 1916. c

posed to construct thelcrown of a backing element 1 and facing element 2, made of dental materials customarily used for such purposes, as for instance, gold, ankrite,

platinum or other metal for the former, and porcelain or other suitable equivalent material for the latter.

Referringto the tooth facing 2, it will be observed that the same presents the general outline and contour of a natural tooth,

The attaching end portion of this facingis preferably formed with a segmental anchor ling recess 3 having a fiat base 4 and an arcuate side wall 5 which latter isintended to be dressed and ground to its final shape or size when fitting it to the 'metallicjbacking. The bOdYfOf the facing has formed therein the longitudinally extending pin receiving sockets 6 which open into the recess 3 approximately at the junction of the side and base walls thereof. These sockets are preferably inclined forwardly from this point toward the biting edge of thefacing, 7

thus occupying an oblique position. rear side of the facing is cut away or'rab- 'beted to provide an abutment shoulder '7,

leaving a reinforcing body of the material as at8 for abutting engagement with the, metal backing .1. w

. The metal backing element 1 preferably comprises a substantially. vertical sheath portion 9 and an inclined cap portion 10, which are so arranged that the former fits flush within the rabbeted or cut away porf I tion at the rear of the facing and the lower edge thereof rests firmly against the abutment 7 while the cap portion fits flush onto the inclined end 10 of the facing. The cap portion 10. of the backing preferably carries a projecting bearing boss or shoulder 11 of solid metalwhose lower face 12 is substantially flat and horizontal like the base 4 of the recess 3, and whose side face 13 is rounded or circular and capable of being easily dressed and ground. to make a snug and'ac curate fit with the correspondingly shaped wall 5 of said recess 3.

Projecting obliquely from one face of the boss 11 is a pair of securing pins 14 adapted to enter and be cemented in the pin-1e.

ceiving sockets 6 of the facing. This pr0- vides a secure anchoring and a rigid interlocking of the parts.

In connection with the pins, 14, it will be apparent that the arrangement and location of the same materially aids in distributing I the ,eilect of the biting force, thereby not only addin to the stability of the portion of the facing farthest from the backing, but strengthening, the entire structure.

Also, since the face 12 of the boss or shoulder ll fiushly contacts with the base a of the recess, the said pins 14 are greatly re lieved of the shearing-stress which would.

otherwise exist, and subject the pins to much strain at time vital point.

The backing element 1 may be provided 1' as shown no Fig. 2-, with a-root-post pin 15 I for the end of thenatural tooth root.-

Regardless of whether the invention isemployed as shown in Fig. 2, or as shown in Fig; l in connection with bridge-work, it will of course be understood that the same general structural features and characteristics of thebackingand facing will beadhered to. That is to say, in all adaptations of the invention, the backing includes the cap and sheathportions' and has on its underside approximately at the junction of said, portions, an enlargement of metal which forms a boss or shoulder. 11 capable Copies of this patent may be obtained forfivecents each, by addressing the Commissioner of Patents,

of being dressed andfittedto thedressed facing cavity orrrece ss designed to receive a I the same This enlargement of the metal I 11 not only provides a firm and solid abut.-

inent to carry the facing securing "pins 114,.

but alsovcooperates with the rounded recess substantial bearing there-for.

In its adaptation for bridge work,; the root-post is of COLllTSfiOllllttEd, and the body portion or plate of thebacking bridged to the'natural' teeth according to the require ments of each case and skill of the dentist:

I claim:

1. A; tooth crown comprising a porcelain or equivalent, facing having a recess provided with a fiat base wall and an arcuate I side wall, and also having; pin receiving sockets communicating with said. recess, and

a inetalbacking having-asolid bearing boss provided with a curved sidewall; and facin the racing :2 to provide an extended and in securin pins carriedb i said bearin boss, said boss andpinsiadaptedto respec-' tively fit into said recess. andp'in receiving:

sockets. I n a 2-. A tooth crown coinprlsing' a porcelain or equivalent facinghaving areccss and pin receiving sockets in communication there-g rs-*ith,-said facing also having a rabbeted portion providing. abutment should 1',-

and a metal backing having agcap portion and a sheath port on, a bearing boss carried, by said backlng, and facing securing pins:

carriedby said bearing boss,- said bearing boss and facing securing pins adapted-to respectively fit into said recess and pinareceiving sockets of the facing, and the. lower:

edge of said sheath portionzfiushly abutting with said shoulder. v v In testimony whereor I hereunto affiX signature in the-presence-of'two Witnesses.-

dVitnessesz; i

Honacn T. SMITH,

Aenns A: Joiinsronr THOMAS H. lVHlTESIDE.

Washington, D. C.

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