US2579960A - Method of making artificial dentures - Google Patents

Description

Dec. 25, 1951 F. PITA ET AL ,9

METHOD OF MAKING ARTIFICIAL DENTURES Filed July 21, 1949 INVENTORS: I fiamfize/l' 25in Julgln Pro/17495 Q a, ww

Patented Dec. 25, 1951 UNITED STATES PATENT OFFICE METHOD OF MAKING ARTIFICIAL DENTURES Frantisek Pita, Jirkov, and Julian Prokes, Chomutov, Czechoslovakia 1 Claim. 1

Artificial dentures are known which comprise an artificial gum adapted to be placed in position on the natural gum, the seating face of the den-: ture being provided with one or more depressions so arranged as to form cavities between the contacting faces of the artificial gum and of the natural gum, the air being exhausted by means of a non-return valve from the cavities so formed. Round studs project from the denture into the cavities in the seating face in such a way that the front faces of the studs abut against the tooth area of the natural gum and are moderately pressed into the latter.

In accordance with a prior invention of the same inventors the cavities or depressions between the contacting faces of the artificial and natural gums are formed by means of suitable interposed elements during the corresponding phase of the process of making the denture. The interposed elements may be originally fiat and made of a soft foil, preferably a lead foil. The interposed elements have a contour anda crosssection of suitable shape and are provided with circular or oval openings, a pair of interposed elements for the right hand and left hand sides of the denture being obtained by dividing into halves a previously made integral piece.

In the making of dentures according to the method just referred to, it has been found that it is not convenient in all cases to divide the foil and that more particularly in the case of irregularly formed gums, especially if the latter are not symmetric with respect to the vertical plane, it is rather difficult to obtain, by means of such two-part foils, cavities in the seating face of the denture in such a way as to comply with the requirements.

The invention described hereinafter permits to overcome the just mentioned difficulty. In accordance with the invention a single foil is employed to shape the cavities for the whole denture, the said foil being provided with slots preferably extending from the circular or oval openings in the foil to the edge of the latter. Experience has shown that by means of foils which have been shaped as described either during their manufacture or supplementally before their use, it is possible to obtain very easily the required cavities not only in normal cases but more particularly also in the case of abnormally formed gums.

For a more detailed description of the invention reference is made to the accompanying drawings, which show an example of the foil and of its utilisation in the method according to the present invention. In the drawings Figure 1 is a section through a lower complete denture and the corresponding part of the lower natural gum along the line A-B of Figure 2;

Figure 2 is a bottom view of the denture shown in Figure 1, the cavities being formed by means of a two-part foil as hitherto used;

Figures 3 and 4 are cross-sections at an enlarged scale through the cavities between the contacting faces of the artificial and the natural gums;

Figure 5 is a plan view of a foil as hitherto used;

Figure 6 is a plan view of a foil provided with slots in accordance with the present invention;

Figure 7 is a plan view of the model of a normal gum on which a foil in accordance with the present invention has been fastened; and

Figure 8 is a similar plan view of the model of an abnormally formed gum.

The artificial denture shown in Figures 1 and 2 comprises an artificial gum l which is adapted to be placed in position on the natural gum 2. Artificial teeth 3 are embedded in the gum I. Between the seating face of the artificial gum and the surface of the natural gum the artificial gum,

has provided therein a series of :cavities 4 which are interconnected and distributed along the entire tooth face of the natural gum and to which a non-return valve 5 is connected. At locations intermediate of the cavities 4 the seating face of the artificial gum l is provided with round studs 6 which are moderately pressed into the natural gum 2 when the artificial gum l is placed in position on the latter. The cavities 4 have an undulated contour in plan view and their crosssection has the shape of a trapezoid as it appears from Figures 3 and 4 which show cross-sections through these cavities at the location of a stud 8 (plane C--D in Figure 5) and intermediate two adjacent studs 6 (plane E-F in Figure 5), respectively, assuming that the seating face has been straightened to a plane.

The above mentioned valve 5 may be constructed preferably in the manner described and shown in the co-pending application Serial Number 105,932 filed July 21, 1949, now abandoned, and relating to an Artificial Denture.

During the production of a denture by the prior method, the cavities 4 shown in Figures 1 and 2 are modeled on the seating face of the denture by means of a foil, such as that shown in Figure 5, provided with circular openings 8 which correspond to the aforementioned studs 6. In the production of, for instance, a complete denture the foil is cut transversely in the plane GH and the two halves after their adaptation to the shape of a gum are fastened on the model of the gum whereby the cavities shown in Figure 2 are obfoil W in Figure 6. In a preferred"arrangement? the slots 9 connect the inner circular openings 8" of the foil with the edge of the latt'er. The slots;

9 may be all of them on the same side; as shown in Figure 6, or alternatingly'on eithen side. as-

shown in Figure 7. v

If the foil is provided with such slots 9during the manufacture of the same, it is prefenah le"toarrange a slot for each of the circular openings 8,. except;- for: the; twd'end; openings: of the; series. If; on. the other; hand; thesslots. are? formed pre-- paratory," to: the; applicatiornof the"; foil: it is: pose siblei to; provide the; slots? only at." such:- locations Where" they arenecessary fnr; the easy. adaptation of the foil to thergum;

The. foil is. appliedtin; the. same: way as? irri the prior method on. the:' surface of; for instance, a plaster'model Isl (cfl Figure" 7) of ..thet'natural gum and is carefully adapted to the form ofthe. latterz. This adaptatiomrwhic'h is very important for a satisfactory operation of the denture to-ber produced is facilitatedz byT'the:s1ots'-:9 providedl in accordance with: theipresent' invention; For the: adaptation. the foil. I is fastened on: the. model ll, for 'iii'stance; bymeansofsmallhails l2 and the further operations are carried out in the'lcon ventional' manner;

Certain toothless natural gums in which a'denture is to be m'ounted have irregular depressions while others again have not a regular' 'contour in plan, being deformed from one of. their sides. In such cases the foil in accordan'ce withthe in vention is most convenient: Figured shows by um whose arcis not symmetrical, as thegum is deformed in its left hand part. The drawing shows clearly that the foil [4 can be easily adapted to such a.gum.

It is possible, of course, to make the slots in the foil according to the present invention in a manner different from that shown and described and still; obtain the aimed. results: Thus; it is not necessary for the" slots to be cut: transversely. They may be inclined to the corresponding transverse planes or may be cut in any other suitable manner..

Whatwecla'iiir is: p

In the method of molding dentures with suction. depressions? in the gum seating surfaces thereof w ith the aid of a foil strip of the size and general shape-of. the depressions to be formed and hav-ing apertures at spaced intervals, the improvement which comprises slotting the foil strip from theapertures therein to one edge thereof, applying the thus slotted foil strip to the mold of: the; gum."- and deforming it:- to; conform; it; to

the contour and..-shapeuofi-thevmold of the. gum in. the position thereomatawhich. the'depressionsiiare to .bevformediin. the .dentureand molding the .den-

ture inicontactwith thermold. of the gum;with.

thefoil strip appliedzther'eom v FRANTISEK RITA.. JULIAN" PROKES;

REFERENGES- CITED- The. following references are of record in the file of'this patent:

UNITED STATES-PATENTS Number Name Date 77,7'73- Smithetal. May 12, 1868 119,245 Shields Sept. 26, 1871'? 729,621 Malone- June' 2, 1903' 940,599 Humphrey Nov; 16, 1909 1,774,907 S'troe Sept. 2, 1930 2,171,736. Ballard Sept: 5, 1939 FOREIGN PATENTS.

N umber Country Date 741,947" France f Dec. 20,- 1932'

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