RU2183106C1 - Method for changing base of removable denture - Google Patents

Abstract

FIELD: medical engineering. SUBSTANCE: method involves coating internal surface of the metal base with retention layer composed of metal identical to one of the base. Acrylic self- hardening plastic materials, cool polymerization silicon, heliocomposite coating internal surface of the prosthesis are useable for changing base. The prosthesis is then mounted in patient mouth. The material for changing base is hardened and the prosthesis is taken from the oral cavity for finishing prosthesis edges. EFFECT: improved fixation conditions; no deposit formation. 3 cl

Description

 The invention relates to medicine, in particular orthopedic dentistry, and for the restoration of removable dentures.

 In modern orthopedic dentistry, the problem of improving the operational properties of removable dentures remains urgent. In the process of using a removable denture, atrophy of the tissues of the alveolar process of the jaw bone adjacent to the prosthesis gradually occurs. As a result, the conformity of the configuration of the inner surface of the base of the removable prosthesis to the tissue relief of the prosthetic bed is violated. This leads to uneven transmission of chewing pressure, which is often the cause of a fracture of the base. In light of the foregoing, in order to increase the service life of a basic denture, it is important to timely identify defects in the denture and relocate it. Relocation is widely used for the restoration of removable prostheses made of acrylic plastic.

 The problem of restoration of removable dentures having a metal base (clasp dentures, partial removable laminar dentures, etc.) remains unresolved to this day.

 A known method of relocation of a removable denture made of acrylic plastic (V. I. Kopeikin, V. A. Ponomareva and others, "Orthopedic dentistry", M., Medicine, 1988, S. 403-405), which consists in that first they examine the jaws and dentures, paying attention to the length of the edges, volume. Then, a plastic layer 1 mm thick is removed from the surface of the prosthesis adjacent to the mucous membrane of the prosthetic bed. For restoration of the prosthesis use self-hardening plastic "Protacryl" and "Redont". The plastic dough in the second stage of swelling ("stretching threads") is applied to the treated prosthesis base in a uniform layer. After 10-15 s, when the surface of the plastic becomes dull, the prosthesis is inserted into the oral cavity, placed on the jaw and pressed, after which the patient closes the jaw. The excess plastic is removed with a spatula, the prosthesis in the rubber-like phase of polymerization is removed from the oral cavity, placed in a special apparatus where the final polymerization of the plastic takes place. The final processing of the prosthesis is to nullify the extruded surplus of plastic. If the patient has contraindications (intolerance to plastic, diseases of the oral cavity), the prosthesis is relocated outside the patient's oral cavity.

 When implementing the above method, a chemical bond is formed between the relocation material and the acrylic base of the removable prosthesis. However, this method of relocation is applicable only to basic prostheses made of acrylic plastics. The choice of relocation materials is also limited. In the case of reconstruction of removable dentures with a metal base, its use is impossible, since a chemical bond cannot form between the relocation plastic and the metal base.

 The main task to which the invention is directed is the restoration of removable dentures with a metal base, the formation of reliable fixation of the relocation material on a metal base and, accordingly, the increase in the life of expensive prostheses with a metal base.

 Our proposed method of relocation of a removable denture is that the denture is relocated with a metal base, on the inside of which a porous retention layer of a metal identical to the base metal is applied by plasma spraying (titanium and its alloys, stainless steel, KHS, gold and its alloys). Acrylic self-hardening plastic, cold polymerization silicone, and heliocomposite are used as a material for relocation.

 When implementing the proposed method, a porous retention layer of a metal powder identical to the metal basis (titanium, stainless steel, KHS, etc.) is applied to the metal base of the restored denture by plasma spraying. The relocation material is spread on the retention layer (acrylic plastic, cold polymerization silicone or heliocomposite) in a plastic state, the prosthesis is placed in the patient’s mouth on the prosthetic bed, after curing the relocation material, the prosthesis is removed from the oral cavity and the edges of the prosthesis are formed in the usual way. Final operations are carried out according to the technology used for acrylic bases.

 In the proposed method, a porous retention layer is applied to a metal base by plasma spraying. The plasma spraying method allows one to obtain a retention layer that is firmly held on the metal surface of the basis not only due to mechanical bonds, but also due to stronger chemical bonds, as well as the development of volumetric interaction (mutual diffusion). The retention layer has transitional properties due to its porous structure, which facilitates its connection with non-metals due to relaxation of surface microstresses. The presence of pores allows you to increase the adhesion force of the restored prosthesis with a layer of material for relocation due to the penetration of plastic material into the pores and the formation of micromechanical bonds.

 The sprayed metal powder should be identical to the base metal, which eliminates the difference in contact electrochemical potentials in the oral cavity and prevents the development of galvanosis. The plasma spraying method allows you to apply powders of various metals, therefore, it is possible to restore dentures with bases made of various dental metals according to the proposed method: stainless steel, titanium and its alloys, KHS, gold and its alloys.

 As materials for relocation, not only acrylic plastic is used, but also other plastic materials: cold polymerization silicone, heliocomposite, which greatly expands the possibility of relocation, for example, when patients are intolerant of acrylic plastic.

 The proposed method allows the relocation of removable dentures with a metal base, which was previously considered impossible. Relocation according to the proposed method can be carried out for various designs of dentures containing a metal base: clasp dentures, soldered removable and partial removable laminar dentures.

 The application of the proposed method allows to increase the service life of expensive dentures with a metal base in 2-3 times.

 The proposed features, namely the application of a porous retention layer on the inner surface of a metal base with subsequent relocation of a denture having a base made of one of the following metals: titanium or its alloys, stainless steel, KHS, gold and its alloys, and use as a material for relocation, in addition to acrylic plastic, silicone of cold polymerization and heliocomposite, was not found in the known technical solutions, which allows us to conclude that the proposed solution It meets the criteria of "novelty" and "inventive level".

 Example 1: According to the proposed method, a partial partial denture denture was relocated with a metal base made of cobalt-chrome alloy. A porous retention layer of cobalt-chrome alloy powder with a thickness of 60 μm was applied to the inner surface of the metal base in a medical plasma system. Then the porous layer was treated with liquid acrylic monomer from the Acryloxide dental kit to pre-impregnate the metal surface and improve its wettability. On the prepared porous layer, a pre-prepared plastic Acryl oxide dough was uniformly applied. After treating the mucous membrane with vaseline in the area of alleged contact with unpolymerized acrylic plastic, a denture was placed on the prosthetic bed, after which the patient closed the dentition in the central occlusion position.

 2-3 minutes after the onset of curing of the acrylic plastic, the prosthesis was removed from the oral cavity. Using a drill, excess surplus material was removed that extruded beyond the metal base. The edges of the base were rounded and polished. The final polymerization was carried out by placing the prosthesis in boiling water for 30 minutes in order to reduce the release of monomer from acrylic plastic.

 Example 2: According to the proposed method, a complete removable denture was relocated with a metal base made of VT-14 dental titanium alloy by superplastic molding. On the titanium base, from the inner side facing the mucous membrane, a porous retention layer of VT-14 alloy powder with a thickness of 70 μm was formed by plasma spraying. To impregnate the porous surface, Protacryl cold-polymerization acrylic plastic was used. "Protacryl" was used in a "liquid consistency" by mixing a liquid (monomer) with a powder (polymer). After complete dissolution of the powder grains in the monomer with a brush, acrylic plastic was applied on a porous surface in a thin layer. After partial polymerisation of the plastic, it was treated with a special Adhesive Haftvermittler adhesive that bonds acrylates to silicones. For relocation, silicone of cold polymerization of VOKO firm (Germany) was used. The silicone mass was mixed with a vulcanizer and applied with a spatula in an even layer on the previously prepared surface of the metal base of the denture. The mucous membrane of the prosthetic bed in the patient’s oral cavity was smeared with petroleum jelly, after which the denture was placed on the prosthetic bed, and the patient closed the dentition in the central occlusion position. 10 minutes after curing of the silicone mass, the prosthesis was removed from the oral cavity and the final polymerization of the silicone mass was carried out by boiling under a pressure of 2 atm for 45 minutes. Correction of the edges of the base in places of excess silicone was carried out after a month of wearing the prosthesis with a cutter at low speed, followed by coating with a special Glazing varnish (Ufi Gel P).

 The proposed method allows to solve the problem of restoration of expensive dentures with metal bases, as well as to facilitate the restoration of prostheses to patients who have contraindications to the use of acrylic plastics.

Claims (3)

 1. The method of relocation of a removable denture, including applying a layer of material for relocation on the inside of the prosthesis, applying the prosthesis in the patient’s mouth to the prosthetic bed, curing the relocation material, removing the prosthesis from the oral cavity and arranging the edges of the prosthesis, characterized in that the relocation is performed on the denture a prosthesis with a metal base, on the inner surface of which a porous retention layer of a metal identical to the base metal is applied by plasma spraying.  2. The method according to p. 1, characterized in that they use a metal base made of titanium and its alloys, stainless steel, KHS, gold and its alloys.  3. The method according to PP. 1 and 2, characterized in that as the material for relocation used acrylic self-hardening plastic, silicone cold polymerization, heliocomposite.