US1444436A - Porcelain veneer crown and process of making same - Google Patents

Description

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F. W. TEETER.

FILED JULY 29,1921.

.ant disadvantages of the latter.

Another object of my invention is to pro Patented Fish. i923.

FRANK W. TEETER, OF LA GRANGE, ILLXNOIS.

PORCELAIN VENEER CROWN AND PROCESS OF MAKING SAME.

Application filed July 29, 1921. Serial No. 483,303.

T 0 all whom it may concern Be it known that l, FRANK V. TEETER, a citizen of the United States, residing at La Grange, in the county of Cook and State of ing same.

In the art of dentistry, it has long been recognized that-many people for aesthetic reasons, obj ct the ordinary full gold crown. To ,veiroine this, porcelain jacket crowns have been used to a limited extent but theporcelain jacket crowns are objectionable for the reason that they require cutting away or trimming of the exposed part of the-teeth to a greater extent than with a gold crown and furthermore, the porcelain jacket crowns are comparatively weak and readily break. An additional objection in connection with the use of porcelain jacket crowns is that, on account of the deep cutting or trimming of the tooth required, it is generally necessary to employjan anesthetic.

One object of my invention is to provide a crown for teeth. which will ossess the advantages of the ordinary gol crown as regards strength,sanitation and light; triinming of the tooth and which at the same time will be free from the objectionable appearance of a full gold crown and be as pleasing, from an aesthetic standpoint as a porcelain jacket crown without vide a novel, simple and eflicient process for produeinga tooth crown of the character indicated in the preceding paragraph.

Other objects of the invention will more clearly appear from the description and claims hereinafter following:

In the drawing forming a part of this specification, Figure 1 1s a perspective view, on an enlarged scale, of a porcelain yeneer crown embodying my invention. Fig. 2 represents a vertical sectional view of an anterior tooth showing my improved crown applied thereto.

Fig. 3 is a diagrammatic view of thepiain blank of gold-plate emthe attend-- ployed in the making of the shell of the crown. Fig. 4 is a perspective view repre senting the second step in the process of making the crown. Figs. 5, 6 and T are per-- spcctivc views representing the third, fourth and fifth steps of the improved process of making the crown. Fig. 8 is a vertical sectional view of the shell of the improved crown prior to the application of the porcelain veneer thereto. Fig. 9 is a view similar to Fig. 8 showing the porcelain veneer in place and. Fig. 10 is a transverse sectional view of the complete crown takennear the base thereof.

Broadly stated, the complete crown enibodies agold shell or crown proper indicated broadly hy the reference A which is made, in accordance with the process hereinafter described, to fit the previously prepared, exposed part of the tooth, said crown proper or shell completely enveloping the prepared tooth. On the labial side of the crown is applied a porcelain veneer or inset designated broadly by the reference B,

parts oi the shell or crown proper being suitably burnished over the edges of the porcelain veneer, the veneer being additionally cemented to the adjacent backing wall of the crown proper or shell A. It will be noted that, in the finished article, a reinforced tip or biting edge (made as hereinafter described) is formed as indicated at l1 and that "the only portions of the gold which will ordinarily be vis ble from the outer or labial side of the teeth will be relatively narrow edge portions of the gold which immediately surround the porcelain veneer so'that the crown may be made to simulate the appearance of t-heenamel of the .original tooth and the contour of the porcelain made to correspond with the surface of the enamel originally on the labial side of the tooth.-

In carrying out my invention, the following procedure is employed. In those'cases where the tooth is set back lingually or inwardly ofthe line of arch, practically no dressing or preparation of the labial side of the tooth} is required since the porcelain veneer may. he made to serve in restoring the normal arch line. In the cases where the tooth to be ground is in the proper arch line. the same is separated at the nterproximal nary gold crown.

-in the usual manner employed with the ordi- 1 1c i cated at 12 in Fig. 2;

partially removed. but ordinarily a thin layer of said enamel may be left as indi- The lingual side of the tooth will ordinarily require no prepa ration since the lingual side ot the crown will be made to tit thereover and. being ofthin metal.preferably ito-gauge. will not- .the gum line is then taken. which will govern the length of the blank subsequently used. Next. a plaster impression of the tooth as prepared is taken. to he used in the making of the crown. Finally. a wax bite or impression is obtained to enable the maker of the crown to properly finish the crown with respect to the biting edge and alincmentwith the tooth of the opposed jaw.

In making the crown. a blank t, of rectangular form and-0t the proper length'and width is taken. as shown in Fig. 3. the blank ordinarily being of 30 gauge ll & S gold sheet metal. The blank is then bent and the edges l3-l3thereof brought together in a.

' butt jiiint as indicated at 13 in Fig. 4 and then soldered so as to produce a substantially cylindrical product as indicated at t" in Fi al. i i

The cylinder C is thencut away on both sides from the top toward the bottom thereot ,so as to provide more or less U-shaped recesses Li and 15 respectively. the size and contouis thereof approximating the labial labial surface of the prepared tooth.

and lingual faces of the. prepared toot-h al-.

though there will be anexcess of the gold left in the form of upstanding prongs 16 and 17, for the purpose hereinafter described.

The article as last described is indicated at C in Fig.

The operator next cuts out a piece of the gold metal indicated at 18 in 'Fig. 6 which corresponds. as nearly as possible. with thti Salt piece 18 is then inserted within the shell C adjacent the recess 1-1 and pushed down into place leaving, however. outwardly extended relatively narrow edge portions 1919 on the sides and rounded portion 21) at the bottom of. the shell manner, the piece 18 is pushed into place within the shell C so as to leave it slightly inwardly inset. The labial piece 18 is then soldered to the. shell around all edges of contact so as to provide a rigid and unitary the shell as C as shown in Fig.

Stated in another 6 is then treated so as to bend the prongs 16 and 17 inwardly toward each other over the upper edge :ZLof the labial piece 18, the prongs l6 and '17 being of such length that they will overlap. as shown at 16 andl'l'" in Fig. l. The overlapped portions thereof are then soldered with a. lapped joint and the prongs in turn soldered to the edge 21- ot' the labial piece 18. By providing a' lapped joint for the prongs 16 and 1' 7, as described. it is evident that the tip or biting edge of the crown is materially strengthencd and itiords a greater amount of metal to take care of the wear thereon.

The shell in theform as last described and as indicated at C" in Fig; 7; then has applied thereto a suitably cutpiece of the gold sheetmetal corresponding to the lingual surface of the prepared toot-h. said piece being indicated at 22 in Fig. 8. The lingual piece :22 is titted within the remaining opening on the lingual side of the shell C and soldered substantially flush with the edges defining the recess 15 and the lapped prongs 16 and 17. As will be understood by those skilled in. the artthe. solder is applied from the insideof the she-ll and naturally there will be an appreciable collection of the solder within the tip of the shell as indicated at 23 in 8 and 9, which will further strengthen the biting edge of the crown.

recess that has been left on the shell onthe labial side thereof. .Cement will be employed between the wall orpiece 18 of the shell and the inner faceof the porcelain and thereafter the projecting edges l9and 20 on the labial side of the shell will'be burnished over the edges of the poroelain veneer. producing the finished veneer crown as shown in Figs. 1. 2. t) and 10.

'llie crown proper or shell at this stage of its i In the drawing, I have illustrated a crown and process of making the same as employed for a central. lVhere 'the or'own. is to be applied to it posterior tootlathe process will be varied slightly so as to employa butt joint instead of the lapped joint for the" prongs 16 and 17 and in addition a cusp piece will be soldered on to the end of the shell. I

Among other advantages of my improved porcelain veneer crown, not heretofore men-. tioned. are the following. lVhei e the crown is to be used as a bridge abutment, the shell without the porcelain veneer may be applied tothe prepared tooth and all attachments made thereto after which the porcelain ve neer may be readily applied and secured in place, by

thereover. Furthermore, in the eyent the porcelain veneer becomes broken, it may be readily replaced without removing the shell portion of the crown from the tooth which is of the utmost importance to the wearer of the crown since it does not interfere with the use of his tooth while the new part is being made.

I have herein shown and described what I now consider the preferred manner of carry .i'ng out the invention.

All changes and modifications that come within the scope of the claims appended hereto, are contemplated.

I claim 1. The herein described process of making a porcelain veneer crown for a tooth which consists in the following steps: taking a blank of gold sheet metal of rectangularform and of proper size; bending said blank into substantially cylindrical form .nd soldering the meeting edges thereof. with a butt joint; cutting out portions of said cylindrically-formed blank on the sides thereof corresponding to the labial and lingual sides of the tooth; shell adjacent the labial recess thereof, a labial wall of gold metal; bending over the projecting prongs of' the cut shell and soldering said prongs over and to the adjacent end of said labial Wall; soldering to the shell thus formed within the labial recess, alabial wall of gold sheet metal; preparing a porcelain veneer corresponding to the labial surface of the tooth; cementing said veneer to said labial wall of the shell; and then burnishing the edges ofthe shell surrounding the veneer over the edges of the latter.

2. The herein described process of mak ing a porcelain veneer crown for a tooth which consists of the followlng steps: preparing a hollow sheet metal shell to conform to and adapted to completely envelop the protruding portion of a previously preburnishingthe edges of the shell 'within the offset j substantially soldering to said out pared tooth, said shell having walls on the labial and lingual sides thereof, the wall on the labial side being inwardly offset; reinforcing the biting edge of the shell; preparing a porcelain veneer corresponding to the labial surfaceof the tooth; inserting said veneer on the labial side of said shell provided by said inset labial. wall of the shell; 'the edges of the shell surrounding said inset in said labial wall thereof over the edges of the porcelain veneer.

3. As an article of manufacture, a porcelain veneer crown for a tooth comprising: a hollow sheet metal shell conforming to and adapted to envelop and fit over the exposed portionof a previously prepared tooth, said shell having an inset wall on the labial side thereof extending from the base to the biting edge of the crown, the biting edge being formed on the shell and constituting the union between said labial wall and. the lingual wall of the shell of a porcelain veneer mounted on the outer surface of said inset labial wall of the shell and retained in place by the edge portions of the shell surrounding said inset wall, sa-id edge portions being burnished over the edges of the porcelain veneer.

l. As an article of manufacture, a porcelain veneer crown for a tooth comprising: a hollow metallicshell conforming to and adapted to envelop a previously prepared tooth, said shell having a labial wall and a lingual wall united at the biting surface of the crown, the labial wall of the shell being inwardly offset with respect to the surrounding edgeportions of the shell and a veneer rigidly aiiixed to said inset wall within said surrounding edge portions thereof.

In witness that I claim the foregoing l have hereunto subscribed my name this 26th day of July 1921.

FRANK W. TEETER. Witnesses:

P. M. Mansion, ANN BAKER.

and then burnishing

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