RU2786816C1 - Method for obtaining a metal stamp for the manufacture of a stamped crown - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to a method for producing a metal stamp for stamping an artificial metal tooth crown. The mold for the stamp is made in a PVC cup with a full-length wall cut from top to bottom. The glass is filled with liquid gypsum by 1 cm, the gypsum column of the tooth is immersed vertically, with the crown part down to its equator. After the gypsum has hardened, the glass is opened, the composition is removed, and three conical recesses are made along the edge of the upper part of the gypsum base. A separating laboratory component is applied to the surface of the composition, the prepared composition is placed in a beaker, and the entire volume of the beaker is filled with medical plaster. After the gypsum has hardened, the glass is opened, the resulting gypsum mold is removed. On the side surface of the upper cylindrical part of the mold, three cuts are made from opposite sides. A spatula is inserted into one of the vertical cuts and the mold is split, separating the lower part of the mold from the upper without damage. After the metal has hardened, poured into the mold matched and installed in the PVC cup, it is removed from the cup and the four-part plaster mold is opened to form a metal stamp.

EFFECT: increase in the accuracy of manufacturing a crown with a given anatomical shape is achieved.

1 cl, 7 dwg

Description

The invention relates to the field of orthopedic dentistry and concerns the manufacture of dentures. It can be used in orthopedic dentistry, orthodontics and pediatric prosthetics during treatment using stamped metal crowns, stamped orthodontic crowns.

From the prior level of dental production, two methods are known for obtaining a metal stamp: using a metal frame and in a rubber ring.

closest prototypes.

A known method of manufacturing a stamp using a metal frame. Gypsum is kneaded, poured into the frame and smoothed with a spatula. The gypsum column of the modeled artificial tooth is half-immersed horizontally in gypsum and waiting for it to harden. After that, the form is removed from the frame, two recesses are made for the protrusions of the other half of the form to enter into them and lowered into cold water to prevent sticking. Then this structure is again filled with plaster to obtain the second part of the form.

After hardening, the mold is opened (with a hammer), the plaster columns are removed, the two parts of the mold are connected and fixed in a special fixative. Low-melting metal is melted and poured into a plaster mold, into specially pre-made holes. In total, you need to cast two metal stamps to make a crown for one tooth. One for preliminary stamping, the second for final stamping. (Kopeikin V.N., Demner L.M. Dental technology. - M .: Publishing house "Success", 1998. - 416 p., ill. On page 141.).

The disadvantage of the described method for manufacturing a mold for a stamp is that at the moment of opening the plaster mold, the negatively displayed anatomical structures of the chewing surface of the tooth are destroyed. This phenomenon cannot be avoided, because the constructively possible displacement of the part of the mold during opening is such that the convex shapes of the chewing surface of the modeled tooth are an obstacle in the direction of movement of the negative parts of the plaster mold. There is a fracture of the gypsum mold in the area of the modeled hillocks. As a result, the microstructure of the chewing surface of the tooth, recreated for the manufacture of a stamp, is destroyed. Broken off small fragments have to be positioned in place and glued, which is quite difficult to do accurately and requires additional labor.

The closest in technical essence to the proposed one is a method of obtaining a metal stamp in a rubber ring with a diameter of 3 cm and a height of 4 cm. Gypsum of normal consistency is poured into this ring and the tooth is immersed in it in a vertical position with the crown part down. To open the plaster molds, the rubber ring is removed and two vertical cuts are made parallel in the middle of the mold, they are connected by a third transverse cut closer to the base of the mold, but in such a way as not to damage the plaster tooth inside the mold. A spatula is inserted into one of the vertical cuts and the mold is split with a lever-like movement. If the plaster tooth does not lag behind any part of the mold, an additional incision is made on it. The resulting plaster mold is assembled from fragments. Filled twice with molten low-melting metal and opened twice to obtain two dies from one tooth shape. One die is used for preliminary stamping and the other for final stamping. (Zhulev E.N. Fixed prostheses: Theory, clinic and laboratory equipment. - Nizhny Novgorod: NGMD Publishing House, 1995. - 365 p., ill. On page 198.).

The disadvantage of the method closest in technical essence to the proposed method is that the line of gypsum fracture along the lower surface of the mold occurs unpredictably and affects the delicately expressed anatomical structures of the tooth. Broken off small fragments have to be positioned in place and glued, which is quite difficult to do accurately and requires additional labor. Accurate opening of such a mold without new damage becomes impossible, and the associated casting of a second stamp identical in shape becomes even more problematic. The described shortcomings lead to the fact that in the clinic, when using a stamped crown, it is not possible to recreate a relief chewing surface, which forms precise fissure-tubercular contacts with antagonist teeth.

The purpose of the claimed invention.

The main goal of restoration of chewing teeth is functional rehabilitation. Functionality, in turn, is due to the anatomical correctness and accuracy of the manufactured orthopedic form of the tooth crown. The convex and embossed chewing surface forms multiple point contacts with the antagonist teeth, evenly distributing the occlusal load. The contact points should be small in area, providing a quick opening of the teeth during excursion movements of the lower jaw, which is especially important in the treatment of patients during the period of removable and permanent dentition.

The technical result of the claimed invention is to improve the accuracy of manufacturing a crown with a given anatomical shape.

The technical result is achieved by obtaining a gypsum mold consisting of four separate parts, which can be opened without damaging the gypsum. The resulting parts of the mold are easily matched to the original mold for casting a metal stamp, which in turn is necessary for the manufacture of a crown by stamping. The use of the proposed method makes it possible to stamp the chewing surface of the artificial crown more accurately to the given anatomical shape of the tooth, without distortions that occur due to fractures of the plaster mold in places of small pronounced anatomical structures of the chewing surface of the tooth.

A method is proposed for obtaining a stamp corresponding to the shape of a simulated artificial tooth for manufacturing a stamped crown according to its shape. The specified technical result is achieved by the fact that the plaster mold for casting, made by the proposed method, opens freely, this allows you to remove the column of the modeled tooth, combine the four parts of the mold in its original position by installing it in the cylinder and perform the casting of a metal stamp into the resulting empty volume of the mold.

A method is proposed for obtaining a metal stamp for stamping an artificial metal tooth crown, including making a mold from four fragments that open along specified boundaries.

The difference is that the mold for the stamp is made in a PVC glass, which already has a full-length wall cut from top to bottom, the glass is filled with liquid gypsum by 1 cm, the gypsum column of the tooth is immersed vertically, with the crown part down to its equator - the line of the greatest anatomical bulge of the crown tooth, which allows you to further freely remove the column in the upward direction from the hardened lower washer-shaped part of the mold, preventing the fracture of the gypsum above the equator. After the gypsum has hardened, the glass is opened, the composition is removed, three conical recesses are made along the edge of the upper part of the gypsum base for the correct reposition of the three upper gypsum fragments of the mold obtained later, a separating laboratory component is applied to the surface of the composition for unhindered further separation of the column from the mold, the prepared composition is installed in glass and the entire volume of the glass is filled with medical plaster of ordinary consistency flush with its upper edge. After the gypsum has hardened, the glass is opened, the resulting gypsum mold is removed, which has a lower washer-shaped and an upper cylindrical part, three shallow cuts are made on the side surface of the upper cylindrical part of the mold from opposite sides, a spatula is inserted into one of the vertical cuts and the mold is split with a lever-like movement, split lines the cylindrical part of the mold pass exactly along the cut lines, and the lower part of the mold is separated from the upper cylindrical part without damage.

After the hardening of the metal poured into the mold, which was matched and installed in the PVC glass, it is removed from the glass and the four-part plaster mold is opened without damage, obtaining a metal stamp. Re-align the parts of the mold and re-cast the desired second die. The obtained metal stamps are used according to the known method of crown stamping technology.

The technical result of the proposed method is the creation of a technology for obtaining a form during manufacture and work, with which damage to the gypsum material of which it consists is excluded. It does not require additional equipment and materials of the dental laboratory. The PVC cylinder is a packaging container for the polishing paste "Polyset" of a domestic manufacturer, commonly used in a dental laboratory.

With this method of manufacturing and opening the form, damage to the plaster on all surfaces of the parts of the form is fundamentally impossible.

The described method allows you to freely remove the plaster column of the tooth. Align the four parts of the mold to its original position, placing it in a glass and casting a metal stamp. Without damage, open the mold, remove the molded metal stamp. Re-combine the parts of the mold into a glass and cast a second stamp from low-melting metal. If necessary, you can repeatedly do the described operation without damaging the plaster mold.

The essence of the claimed method is shown in figure 1, which shows a modeled plaster column, the classical anatomical shape of the chewing surface, taking into account the antagonist teeth, figure 2, which shows a plastic cup and the composition extracted from it: the lower part of the plaster mold (washer-shaped) with a plaster column of the tooth , in Fig. 3 which shows an unpacked plaster mold with a plaster column of the tooth, in Fig. 4 which shows an unpacked plaster mold with a cast metal stamp, in Fig. 5 shows the resulting stamp for stamping a metal crown; 7 shows the resulting stamped metal crown at the finishing stage in the dental laboratory.

Increasing the accuracy of manufacturing a crown with a given anatomical shape is achieved due to the fact that, unlike the prototype, when using the proposed method of manufacturing and opening the mold, damage to the plaster on all internal surfaces of the parts of the mold is fundamentally impossible. In turn, the low-melting metal stamp obtained in a plaster mold is an accurate reflection of a given tooth shape, without distortions that occur due to fractures of the plaster mold in places of small pronounced anatomical structures when using the prototype method. Therefore, the application of the proposed method allows you to stamp all surfaces of the artificial crown more accurately compared to the prototype method.

Using the proposed method, the technology for the precise manufacture of stamped crowns is improved, which in turn increases the efficiency of treating patients in the clinic of orthopedic dentistry, orthodontics and pediatric prosthetics by increasing the accuracy of manufacturing a crown with a given anatomical shape.

Clinical example.

We give a clinical example of the treatment of patient N., 22 years old, using a stamped metal crown for 4.7 teeth.

Patient N., 22 years old, came to the clinic with complaints about the destroyed crown part of the 4.7 tooth, discomfort on the gums when taking hard fibrous food in the area of the 4.7 tooth.

Anamnesis. 4.7 tooth was treated several months ago due to complicated caries.

Objectively. The face is unchanged. The nasolabial and chin folds are moderately expressed, the height of the lower face is not reduced. Opening of the mouth is free, painless. Regional lymph nodes are not palpated. The mucous membrane of the vestibule of the oral cavity is pale pink, moist, shiny. The bite is fixed, orthognathic. Tooth 4.7: the coronal part was restored with a filling material of satisfactory quality.

Diagnosis. Defect of hard tissues 4.7 teeth. ICD code: K 02.9. Dental caries, unspecified. Medium and deep carious defect in a previously treated tooth.

Treatment using a stamped metal crown for 4.7 teeth.

clinical stage. Justification and choice of design. Odontopreparation of 4.7 teeth. Removal of alginate impressions from the upper and lower jaws.

Laboratory stage. Making models from medical plaster. Plaster casting of models in a mid-anatomical articulator. Cutting a plaster column 4.7 of the tooth with a crown modeled from wax (figure 1). Production of metal stamps by the proposed method. Making the lower part of the form (figure 2). Production of plaster molds in a PVC glass (figure 3). Unpacking a plaster mold with a cast metal stamp (Fig. 4). Obtaining a metal stamp for stamping a metal crown (Fig. 5). Stamping of a metal crown by a combined method in the modification of MMSI. Finishing, grinding, polishing. Finished crown for transfer to the clinic (Fig. 7).

clinical stage. Fixation of the crown on dental phosphate cement. The treatment of the hard tissue defect of the 4.7 tooth was completed with the restoration of the anatomical shape.

Claims (1)

A method for producing a metal stamp for stamping an artificial metal tooth crown, including making a mold from four fragments that open along specified boundaries, characterized in that the mold for the stamp is made in a PVC cup that already has a wall cut in its entire length from top to bottom, the cup is filled with liquid gypsum on 1 cm, the gypsum column of the tooth is immersed vertically, with the crown part down to its equator - the line of the greatest anatomical bulge of the tooth crown, which makes it possible to further freely remove the column upward from the hardened lower washer-shaped part of the mold, preventing the gypsum from breaking above the equator, after the gypsum has hardened, the glass open, the composition is removed, three conical recesses are made along the edge of the upper part of the gypsum base for the reposition of the three upper gypsum fragments of the mold obtained later, a separating laboratory component is applied to the surface of the composition for unobstructed after further separation of the column from the mold, the prepared composition is placed in a glass and the entire volume of the glass is filled with medical plaster flush with its upper edge, after the plaster has hardened, the glass is opened, the resulting plaster mold is removed, which has a lower washer-shaped and an upper cylindrical part, on the side surface of the upper cylindrical parts of the mold make three cuts from opposite sides, a spatula is inserted into one of the vertical cuts and the mold is split with a lever-like movement, while the split lines of the cylindrical part of the mold pass exactly along the cut lines, and the lower part of the mold is separated from the upper cylindrical part without damage, after the metal has hardened, poured into a mold matched and installed in a PVC glass, it is removed from the glass and the four-part plaster mold is opened without damage, obtaining a metal stamp.

Images