RU2197919C2 - Method for manufacturing hollow obturator of maxillary resection prosthesis - Google Patents

Abstract

FIELD: medical engineering. SUBSTANCE: method involves carrying out packing and polymerizing under pressure in vertical and horizontal direction in a cell at the same time. The cell has lateral opening, slide valve and screw with external handle on one side and disk on the other side. Mold model is produced in the cell in horizontally placing the mold by filling lower and upper part of the cell in turn until gypsum hardens in each of them. The cell is disassembled so that a half of the model is in each cell part. Trapezoid stem is formed by connecting both halves of the cell and cutting out the stem in gypsum connecting model base with the lateral cell opening. The cell is opened into two halves and obturator is modeled from wax of predefined wall thickness. The cells halves are joined and gypsum is poured into the lateral opening. The gypsum is hold until its full hardening. The cell is opened and wax is removed by evaporating and gypsum stamp is produced. Then supporting stamp is manufactured. To do it, gypsum stamp with congruent surface is placed in the lower half of obturator model positioned in cell base with closed bottom. An auxiliary cell is used. This cell is a copy of upper cell part with cover. The auxiliary cell is put on over cell base and sand is supplied into it so that the protruding portion of the gypsum stamp is retained above the sand surface. The auxiliary cell is filled with gypsum and protruding portion imprint is produced after its being hardened. Two-staged packing is carried out. Paste-like plastic is poured into lower model part placed in the model base at the first packing stage. Gypsum stamp with congruent surface is placed over it and covered with the auxiliary cell with supporting stamp. The protruding gypsum stamp is superimposed over the supporting stamp. Packing is carried out in vertical and horizontal direction at the same time. Paste-like plastic is poured into the rest of the model placed in the upper part of the cell at the second stage. The second stage is completed in joining both cell parts. Packing takes place both in vertical and horizontal direction simultaneously. Then plastic polymerization takes place. EFFECT: uniform pressure distribution. 8 dwg

Description

 The invention relates to dentistry and is intended for the manufacture of an elastic hollow obturator with a wall thickness of less than 2 mm, used in prosthetics for complete resection of the upper jaw in the presence of mild or absent retention points of the defect.

 A known method of manufacturing a hollow obturator of a resection prosthesis of the upper jaw by injection molding (see E. Ya. Vares, V. A. Nagurny. Centralized manufacture of dentures using a new and improved technology. Plastic pressing. Zhytomyr, 1992, p. 53 -155) [1] made of rigid plastic material of the Ftoraks type. According to the method, a cast of the defect is taken, the model is cast, the wax template is modeled, the model is plastered in a syringe cuvette and the plastic is molded under vertical pressure. In this case, two hemispheres of rigid plastic are obtained. Then they are glued together and a finished obturator is obtained, resembling a sphere that cannot exactly repeat the configuration of the postoperative defect of the upper jaw. However, using the described method, it is impossible to obtain a hollow, elastic obturator with walls of a given thickness with a relief-shaped spatial configuration corresponding to a postoperative defect. This is due to the fact that since the vertical pressure through the gate during the manufacture of the obturator with a relief-shaped spatial configuration, the force of this pressure cannot be uniform at all points of the future wall of the obturator, and therefore, where the pressure force is insufficient, a defect is formed in the wall.

 In addition, in the described method it is impossible to use elastic plastic, because You cannot glue two hemispheres.

 There is a method of molding dental and maxillofacial prostheses from plastics by conventional pressing, which consists in taking a mold, obtaining a model from it, modeling a wax obturator template, plastering a model with a wax template in a cuvette in a vertical position, packing and polymerizing plastic in a vertical direction (see V.N. Kopeikin, J.S. Knubovets, V. Yu. Kurlandsky, I.M. Osman, Dental prosthetics, chap. 8, 9, art.Plastic application technology.M .: Medicine, 1978, pp. . 105-109; 272-275.) [2], taken as a prototype.

 In this case, a cuvette containing a base, a base bottom, an upper part and a lid equipped with slots and protrusions for fixing the detachable parts is used [2], p. 106.

 The disadvantage of this method using the described cell is the manufacture of only monolithic obturators in the form of a hemisphere for a resection prosthesis of the upper jaw, because packaging and polymerization in the vertical direction do not provide uniform pressure on all points of the manufactured obturator.

 The objective of the invention is to develop a method of manufacturing a hollow obturator of a resection prosthesis of the upper jaw with a wall thickness of less than 2 mm, used in the presence of mild or absent retention points of the defect.

 The technical result of the invention is to ensure uniformity of pressure on all points of the manufactured obturator during packaging and polymerization.

 The technical result is achieved in that a method of manufacturing an obturator of a resection prosthesis of the upper jaw using a cuvette by taking an impression of a defect in the upper jaw, obtaining a model from it, modeling a wax pattern of the obturator, packing and polymerization in the vertical direction, according to the invention, the packaging and polymerization are carried out in a cuvette equipped with a side hole, a slide gate and a screw with an external handle on one side and a disc on the other.

 The model of the impression is obtained directly in the cuvette with horizontal placement of the impression by alternately filling the lower and upper parts of the cuvette until the gypsum hardens in each and its subsequent connectors. At the same time, half of the model will be placed in each part, then a trapezoidal shank is formed by connecting both halves of the cuvette and cutting a trapezoidal shank in gypsum connecting the base of the resulting model with the side hole of the cuvette. After that, the cuvette is opened into two halves and an obturator with a given wall thickness is modeled from wax on the model. The halves of the cuvette are connected and gypsum is poured into the side hole, kept until completely solidified, the cuvette is opened and the wax is removed by evaporation. This produces a stamp of gypsum. Then, a support stamp is made, for which a gypsum stamp with a congruent surface is placed in the lower half of the obturator model, located at the base of the cell with a closed bottom. In this case, an auxiliary cuvette is used, which is a duplicate of the upper part of the cuvette with a lid. Put on the base of the cuvette an auxiliary cuvette, pour sand into it so that the protruding part of the gypsum stamp remains above the surface of the sand.

 Next, the auxiliary cuvette is poured with gypsum and, after hardening, an imprint of the protruding part of the gypsum stamp is obtained. Then carry out a two-stage packaging. Why, at the first step of packaging, dough-like plastic is poured into the lower part of the model, located at the base of the cell. A gypsum stamp is laid on it with a congruent surface and covered with an auxiliary cuvette with a support stamp and the protruding part of the gypsum stamp with a support stamp is combined. Packing is carried out in vertical and horizontal directions at the same time. At the second stage of packaging, the doughy plastic is poured into the remaining half of the model, located in the upper part of the cuvette, and after connecting the two halves of the cuvette, the second packaging step is carried out, which is also carried out simultaneously in vertical and horizontal directions. Then carry out the polymerization of plastic.

The operation of the method is illustrated by figures, where:
figure 1 is a schematic drawing of a cuvette for the manufacture of an obturator;
figure 2 is a schematic drawing of an auxiliary cell for the manufacture of a supporting stamp;
FIG. 3 is a diagram of the gypsum plaster cast of a postoperative cavity in a cuvette (vertical section);
FIG. 4 is a diagram for obtaining a model of a postoperative cavity and a trapezoidal shank (vertical section);
FIG. 5 is a diagram for obtaining a wax pattern of an obturator and a gypsum stamp (vertical section);
FIG. 6 is a diagram for obtaining a support stamp in an auxiliary cuvette (vertical section);
FIG. 7 is a diagram of the first step of packaging using an auxiliary cuvette and a support stamp (vertical section);
FIG. 8 is a diagram of a second step of packaging in a cuvette (vertical section).

 The method is carried out using a cuvette (Fig. 1), which allows for packaging and polymerization under pressure in the vertical and horizontal directions at the same time, which contains a base 1, a bottom of a base 2, an upper part 3 and a cover 4 provided with grooves 5 and protrusions 6 for fixing detachable parts of the cuvette, a slide gate 7 provided with a press screw 8 with an external handle 9 on one side and a press disk 10 on the other. An opening 11 is made in the side of the cuvette to place the press disk 10. On the side of the cuvette, there are two guides 12 for moving the slide gate 7 in the vertical plane and a limiter 13 for moving the slide gate 7. The auxiliary cuvette (figure 2) is a duplicate of the upper part of the cuvette and consists of a housing 14 and a cover 15, also provided with grooves 16 and protrusions 17 for fixing the detachable parts and connecting the housing 14 of the auxiliary cell to the base of the cell 1. There is a semicircle in the side of the auxiliary cell nd bore 18 and two guides 19 to move the slide valve 7 in the vertical plane.

 The operations of the method are as follows.

 A cast of the defect is taken with alginate masses, gypsum is placed in a horizontal position in the cuvette (Fig. 3), a model of the upper jaw defect in the cuvette of the obturator of the maxillary resection prosthesis is obtained (Fig. 4), a trapezoidal shank is cut that connects the base of the obtained model with the side opening of the cuvette 11 , and model the wax pattern of a thin-walled obturator (Fig.3). After this, a stamp is made of gypsum, repeating the spatial configuration of the postoperative defect of the upper jaw, reduced by the wall thickness of the wax pattern of the obturator.

 Obtaining a reference stamp (Fig. 6). To do this, in the lower half of the obturator model, located at the base of 1 cuvette with a closed bottom 2, a stamp of gypsum is placed with a congruent surface.

 An auxiliary cuvette is used, which is a duplicate of the upper part and lid of the cuvette, where there is a casing 14 and a lid 15 provided with slots 16 and protrusions 17 for fixing the detachable parts (casing 14, lid 15, cuvette base 1). In the lateral part there is a semicircular hole 18 and two guides 19 for moving the slide gate 7 in a vertical plane.

 Put on the casing 14 of the auxiliary cuvette and fill the sand into the casing 14 so that the protruding part of the gypsum stamp remains above the surface of the sand.

 Gypsum is poured onto the sand, covered with a lid 15 and allowed to solidify, remove the auxiliary cuvette from the base 1 of the cuvette, remove the stamp from the gypsum and pour sand, which is obtained in the auxiliary cuvette, the reference stamp is the imprint of the protruding part of the gypsum stamp.

 The first step of packaging.

 1. In the model located at the base of the cell 1 pour pasty-like plastic type "elastoplast".

 2. Place a stamp of gypsum with a congruent surface in the specified model.

 3. The base of the cuvette 1 with the bottom 2 placed in it by a gypsum stamp is covered by the body 14 of the auxiliary cell with a lid 15 with a supporting stamp located in it, which at the same time, the protruding part of the gypsum stamp is combined with the supporting stamp in the auxiliary cell.

 4. Create vertical and horizontal pressure at the same time (Fig.7) while the paste-like mass of plastic is uniformly compacted, its excess is displaced.

 5. Then remove the auxiliary cuvette, remove excess extruded plastic.

 The second stage of packaging.

 6. In half of the model, located in the upper part of the 3 cuvettes, pour pasty plastic and connect the two halves of the cuvette, and therefore, the model, in one piece.

 7. At the same time, they act with vertical and horizontal pressure (Fig. 8), while achieving uniform pressure on all points of the manufactured obturator. Since the plastic was already compacted at the first packaging step in the base of the 1st cuvette, the first kind of lever does not appear at the second packaging step, therefore, the pseudo-stamp does not shift relative to the model and further polymerization prevents defects in the wall of the obturator located at the base of the 1 cuvette, which allows eliminate the formation of wall defects, reduce the thickness of the walls of the obturator to 2 mm or less than a resection prosthesis of the upper jaw.

Sources of information
1. E.Ya. Vares, V.A. Nagorny. Centralized denture manufacturing using new and advanced technology. Plastic pressing. Zhytomyr, 1992, pp. 53-155.

 2. V.N. Kopeikin, Ya.S. Knubovets, V.Yu. Kurlandsky, I.M. Oksman. Dental prosthetics, Ch. 8, Art. The technology of plastics. M .: Medicine, 1978, pp. 105-109; 272-275, a prototype.

Claims (1)

 A method of manufacturing an obturator of a resection prosthesis of the upper jaw using a cuvette by taking an impression of a defect in the upper jaw, obtaining a model from it, modeling the wax pattern of the obturator and packing and polymerizing the plastic in the vertical direction, characterized in that the packing and polymerization is carried out in a cuvette equipped with a side opening a slide gate and a screw with an external handle on one side and a disk - on the other hand, the model of the impression is obtained directly in the cuvette with a horizontal dimension forming a mold by alternately filling the lower and upper parts of the cuvette until the gypsum hardens in each and its subsequent connectors, half of the model will be placed in each part, then a trapezoidal shank will be formed by joining both halves of the cuvette and cutting the trapezoidal shank connecting the base of the resulting model with the side hole of the cuvette, after which the cuvette is opened into two halves and an obturator with a given wall thickness is modeled from the wax on the model, the halves of the cuvette are connected to the side the hole is poured into gypsum, maintained until completely hardened, the cuvette is opened and the wax removed by evaporation, this produces a gypsum stamp, then a support stamp is made, for which purpose a stamp from congruent gypsum is placed in the lower half of the obturator model, located at the base of the cell with a closed bottom surface, using an auxiliary cuvette, which is a duplicate of the upper part of the cuvette with a lid, put an auxiliary cuvette on the base of the cuvette, pour sand into it so that the protrusions the majority of the gypsum stamp remained above the surface of the sand, then the auxiliary cell was filled with gypsum and after it hardened, an imprint of the protruding part of the gypsum stamp was obtained, then two-stage packaging was carried out, for which, at the first stage of packaging, the pasty was poured into the lower part of the cell plastic, a gypsum stamp is placed on it with a congruent surface and covered with an auxiliary cuvette with a support stamp and the protruding part of the gypsum stamp with a support stamp is combined, pa The bag is carried out in vertical and horizontal directions at the same time, at the second step of packaging, the doughy plastic is poured into the remaining half of the model, located in the upper part of the cuvette, and after the two halves of the cuvette are joined, the second step of packaging is also carried out, which is also carried out simultaneously in vertical and horizontal directions, then polymerisation of plastics.

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