US2099454A - Dental matrix - Google Patents

Description

Nov. 16, 1937. l. E. SIQVELAND ,0

DENTAL MATRIX Filed March 25, 1935 4 16," 16" 13 v d I? i 5 B 5 1 ,44

Fifi F4946 1 v 2,099,454 I DENTAL MATRIX Ivar E. Siqveland, St Paul, Minn. n lieatiii imaiciiz's, 1935, Serial No. 12,873

1 claims. (cl; 2 's) This invention relates to the method of making eryic hend theri 1ax and..:plasticl.fillin s iorteethaan tt emeans .o .Qbtaining virtually are t was m res i n or p e o e i U s mple ma nerit u carryin out a fin r hn qu ma ng c vical and other inlays orfillings .qipr w t;:haebeen; f icult to obtain. the W simnr n;..of thes avityiowins t t e fact 2 t t e-waxsim ress n. patte n, 9 161 not he di v emqre t Wi ho s i le d tort on or ju y hereto e nthel mpre onl Wa was Plates he ee the, too hla th m-a heated sp ee-inse te i e h wax. with, h s 3114 ni hQdr-thmsri u wash sin ce; il

tl iewax had set about thesprue and then the wax ,impressio ywas removed on n of t e spr 1e, Itwill beapparent that unlessthe dentist w iextr m l ca e u th s ol method, h m ehti iu e, thea rm or a e. o h a im:

pre ssionpr. pattern; in inserting the sprueiand try ngl toremove it .from the cayity. This I have entirely overcome with my method by-providing waxed sprues of, the desired character for difierent .cavities',iand apparatus for insertingthe waxed'sprue, intolthe' cavity so as to obtain a virtually perfect wax. impression. I a feature of vmy method resides in providing waxed sprues of different shapes'and characters so that they may be readily adapted to difierent cavities-"These waxedsprues are in the form V of a short wire having the impression wax formed in-thedesired shape on one end thereof; Inone form, the-impressionwax on the sprue may be conical'so that the apex thereof may assist in guiding the wax. into the -cavity.= In another form the;wax;may -be cylindrical on one. end of theli sprue-nwire ior .tof such other shapelas. may desired: These; shorth-wireysprues with the waxed ends are; supplied to; the dentist "in-the quanti y-an s pe es -c 1 v :i ,Jl 'he inventionincludes a suitable matrix plate havingfa tubular supporting; portion through which the outer end OfJthe sprue may extend.

1 lnQcalfrying but my 'method, I provide a V suitableljiorming' tool for, forming, the matrix. plates to the outer contour'of'the 'tooth to be filled.

I also provide an applying tool for holding. or supporting the matrix plate with ,thespru'e pin extendinggthmugh the same and the-waxed end of thesp rue adjacent tothe matrix plate. This applying tool holds. the matrix "plate and sprue in applying position and is provided with a springprged socketintowhich the-end of ;the smile Pil fit J fl a p y n tool permits th waxed sprue to be pressed by the matrix plate into the cavity, thev matrix'plate fitting closely to the outercontour, of the tooth and pressing the impression wax into the cavity firmly, so as to obtaina true-impression of the cavity while 5 the impression wax is soft-enough to be pressed into the same. The springurged socket'which engages the end of the sprue pin ejects the sprue as; the applying vtool isdrawn away from the tooth and thesprueipin remains projecting from 10 the (impression which has become set in the cavity in the tooth ,Then when-the impression wax is sufficiently set with the sprue pin anchored therein and projecting. therefrom, the mold may tool. holds the-same, in position until the impression wax has. thoroughly set. p

, Myvmethod providesabetter dental technique in themakingof surface fillings on the outer faces ofteeth, such vas cervical and-other inlays and plastic fillings. The applying tool with the matrixplate may be used} to apply the plastic fillings in a more efiicient manner than'has been accomplishediheretofore.. The features-of .my method of making cervical and other inlayand plastic fillings will be more fully apparent from the disclosure of the tools desirable in, carrying out the same and the mannerin which,- the waxed sprues are handled and applied-to. obtain the desired impression of the cayity. 1

The drawing is for the purpose of illustrating the, carrying out of my method and showing the apparatus, such as the tools desirable, and the 40 construction ofthe waxedsprues-and matrix plate as used inone form in carrying out my method.- y t g i In the drawing, Figure 1 is a side elevation of a setof upper and lower teeth in biting position, showing acavity which is about to be filled by mymethodw r; I v

Figure 2 is a perspective view of the matrix plate'iused in carrying out my method.

-,Figure 3 illustrates the bending and shaping pliers used for holding and .forming the matrix 1 plate'to the. shape of the-tooth. i;

Figure lnillustrates almatrix plate bent into the desiredshape. l a v v. Figure 5.illustrates a waxed sprue of one form.

Figure 6 illustrates a waxed sprue of another form.

Figure '7 illustrates a waxed sprue of still another form.

Figure 8 illustrates the applying tool with a waxed sprue and matrix plate held as a unit and ready for taking an impression of a cavity in a tooth.

Figure 9 is a sectional detail of the operating end of the applying tool, showing its position in taking an impression of a cavity in a tooth and showing the manner in which the matrix plate. operates to press the impression wax into the.

cavity and showing the position of the sprue pin in the applying tool cushioned by the spring means in the tool.

Figure 10 is a section of a tooth, which shows the impression wax with the sprue pin projecting therefrom after the impression of the cavity has been taken and the applying tool with the matrix plate has been withdrawn from the tooth.

Figure 11 illustrates a perspective of the removed sprue pin and impression after the wax impression of the cavity has been taken by my method, as illustrated in Figures 9 and 10.

Figure 12 is an enlarged section of a waxed sprue.

In carrying out my method of making cervical and fillings of a similar character, I use a matrix plate III which is formed of thin sheet metal or other suitable material, such as celluloid. This matrix plate It is provided with a tubular shank II having a hole I2 extending through the same.

The matrix plate I is adapted to be cut with the desired peripheral shape and may be formed by supporting the same in the holding pliers with the shank II extending in the slot I3 of the bifurcated end of the pliers A as illustrated in Figure 3. One of the jaws I4 of the pliers A may be round in cross-section so that the matrix plate I0 may be formed around the same while it is held between the jaws of the pliers A.

To assist me in further carrying out my method I employ waxed sprues B, illustrated in Figures 5, 6 and '7. The sprues B consist of a wire shank I on one end of which a body of wax I6 is formed in any desired shape. Thus I provide a waxed sprue B with a wire shank I5 and with a body of wax such as I6 in spherical form, I6 in conical form, or such as in the form illustrated by I6", or in any other shape that may be desired. These sprues B may be furnished to the dentist in any quantity and shape that he desires.

The advantage to the dentist in having waxed sprues B with the impression wax on the end of the same will be apparent in that the dentist may take a sprue of the desired shape and size for the respective cavity and secure an impression of the cavity to be filled very readily.

Further, my method is carried out by the use of the applying tool C which is formed with a handle portion II from which projects the operating arm I8. On the working end of the operating arm I8 I provide a cylinder I9 in which is located a coil spring 20 which is adapted to resiliently position the socket 2| within the cylinder I9 so as to normally urge the socket 2I toward the tubular collar 22 which is positioned in the outer end of the cylinder I9. The collar 22 is formed with an axial opening 23 which is adapted to receive the shank II and the sprue B collectively, as illustrated in Figures 8 and 9.

In carrying out my method of making cervical and other fillings in the operation of securing the impression of the cavity in the tooth, the

matrix plate I0 is formed into the desired shape by first trimming the edge of the plate III to the shape desired and then forming the same while held by the pliers A. Then the desired sprue B is placed with its shank I5 extending into the shank I I of the matrix II] and then this unit consisting of the matrix and sprue, is placed into the sleeve-like collar 22 of the applying tool G. Then the dentist is ready to take an impression of the cavity 24 and this is done by having the impression wax I6 warm. enough to readily form itself to the shape of the cavity and then by taking the applying tool C and pressing the matrix plate I0 against the outer surface of the tooth D forcing the impression wax into the cavity 24 firmly, and as soon as the same has set, the applying tool is withdrawn, whereupon the impression wax I6 will remain in the cavity 24 and the pin I5 of the sprue B will project from the same as illustrated in Figure 10. The dentist may then remove the sprue B with the wax impression E of the cavity 24 formed thereon as illustrated in Figure 11. It will therefore be apparent that with my method of securing the impression of a cavity to be filled, a dentist may accomplish the same with a finer technique than was possible heretofore and with full assurance of obtaining virtually a perfect wax impression of the cavity in the tooth such as D. Heretofore, the dentist could not carry out this fine dental technique, not being advised of my method or manner of carrying out the same, and not having the waxed sprues, matrix plate or applying tool it was not possible for the dentist to easily obtain a virtually perfect impression of the cavity to be filled. With my method, cervical and other fillings may be made very readily by the dentist with full assurance of obtaining a perfect impression of the cavity, and the wax impression is easy to handle owing to the fact that the sprue wire I5 is firmly embedded in the central portiorr.

of the impression.

The wire shank I5 of the sprue B may be threaded or formed with a roughened end at I5 so as to more firmly hold the wire shank I5 embedded in the wax I6. Therefore, my method of making cervical and other fillings comprises preparing a matrix plate to the desired shape, connecting a waxed sprue with the matrix plate so that they may be operated as a unit, then supporting this unit of matrix plate and sprue in a manner to permit the impression wax to take a true impression of a cavity to be filled. When the impression is taken, the sprue wire permits the easy removal of the wax impression of the cavity without distorting or injuring the impression and then the dentist may cast a true inlay. Further, the method provides a means of making plastic fillings by using the matrix plate to support the plastic filling and then with theapplying tool forcing the plastic filling into the cavity. Thus I provide a method wherein the finest dental technique may be accomplished in, making fillings of the character set forth, with the greatest of ease. I j

I claim:

1. A matrix for filling dental cavitiesincluding a flexible plate formed to the curvature of the tooth, and a hollow shank secured thereto providing an opening entirely through the shank and plate. Y

,2. A matrix for supporting wax including a plate of soft material flexible to fit the curvature of a tooth, and a shank projecting from one surface thereto having an opening extending through said shank and plate.

3. A cavity filling means comprising a matrix plate to fit the outer conformity of a'tooth, said plate having an opening therein, and means supporting cavity filling material adjacent said plate including a sprue extending through said opening having cavity filling material on the end thereof.

4. A cavity filling means comprising a matrix plate to fit the outer conformity of a tooth, a shank thereupon, said shank having an opening therethrough extending also through said plate, and means for supporting impression material adjacent said plate including a sprue bearing impression material extending through said opening.

IVAR E. SIQVELAND.

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