RU219958U1 - Device for fixing a removable denture - Google Patents

Abstract

The utility model relates to medicine, namely to orthopedic dentistry, and is intended for fixing removable dentures (lamellar, clasp and removable bridges) with telescopic crowns. The essence of the proposed utility model is as follows: it contains a device for fixing a removable denture, containing an inner, outer crown and an intercrown retainer, characterized in that the intercrown retainer is made of an elastic elastic material and is placed over the entire inner surface of the outer crown, not reaching 2 mm to its edges, moreover, the thickness of the elastic material in the non-working position is 0.4 mm, and a circular ledge is formed on the edge of the outer crown to protect the elastic retainer of the outer crown, which can be attached to the base of the removable denture.

Description

The utility model relates to medicine, namely to orthopedic dentistry, and is intended for fixing removable dentures (lamellar, clasp and removable bridges) with telescopic crowns.

A device for fixing telescopic crowns to each other, consisting of friction pins and guide bushings (Lebedenko I.Yu. et al. Telescopic and locking fastenings of dentures. - M.: Young Guard, 2004.- S. 71-73).

Device disadvantages:

1. Deformation of the friction pins is possible when applying the prosthesis.

2. The pins may break and the friction pins cannot be replaced.

3. The need for additional equipment (plasma welding, spark erosion).

It is also known a device for fixing telescopic crowns, made in the form of a plunger (spring-loaded metal ball) (Lebedenko I.Yu. et al. Telescopic and locking fastenings of dentures. - M .: Young Guard, 2004. - S. 70, Fig. 61 ). This device is taken as a prototype.

Device disadvantages:

1. At the place of installation of the plunger, the crown must have a significant thickness, which creates bulkiness.

2. Special precision is required to form a recess on the inner metal crown to snap the ball.

3. The complexity and laboriousness of pressing the plunger into the wall of the crown.

4. Difficulty or even impossibility of replacing the plunger if the spring breaks.

The purpose of creating a utility model is to increase the wear resistance of an elastic intercoronal fixator and extend its service life.

The essence of the device for fixing a removable denture: contains an internal, external crown and an intercrown retainer, characterized in that the intercrown retainer is made of an elastic elastic material and is placed along the entire inner surface of the outer crown not reaching 2 mm to its edge, and the thickness of the elastic material in the non-working position is 0.4 mm, and a circular ledge is formed on the edge of the outer crown to protect the elastic retainer of the outer crown, which can be attached to the base of the removable denture.

The utility model is schematically illustrated by graphic material (in enlarged form): in Fig. 1 shows a general view of the inner crown on the stump of the tooth (longitudinal section); in fig. 2 shows a longitudinal section of an external crown with an elastic retainer; in fig. 3 shows a longitudinal section of the inner and outer crowns with an intercrown fixator; in fig. 4 - cross-section of both crowns with an intercoronal fixator on the stump of the patient's tooth at the level of the middle of the crowns (section along A-A) in working condition.

The device for fixing a removable denture contains an internal crown (2), which is fixed on the stump of the tooth (1) (Fig. 1, 3 and 4). In addition, the device contains an external crown (3) with an elastic retainer (4) and a circular ledge (5) at the border of the external crown (Fig. 2, 3 and 4), which is attached to the base of the removable prosthesis according to a known method.

A device for fixing a removable denture is used as follows.

On the stump of the tooth - 1 (Fig. 1) make a primary cast metal crown - 2 (Fig. 1). The outer crown - 3 (Fig. 2) is made on the inner crown - 2 (Fig. 3) and is attached to the base of the removable denture in a known manner. Further, retreating 2 mm from the edge of the outer crown - 3 (Fig. 3), the inner surface of the outer crown is removed with an abrasive tool to a thickness of 0.4 mm. At the same time, a circular ledge - 5 (Fig. 3) is formed on the edge of the outer crown, designed to protect the elastic retainer - 4 (Fig. 3). After that, micro-roughness is created on the treated inner surface of the outer crown by sandblasting, an adhesive is applied that will ensure adhesion of the elastic material to the metal surface. Then cold polymerization plastic is prepared (for example, Orthosil-M), which is used to fill the outer crown - 3 (Fig. 4). The outer crown - 3 (Fig. 4), filled with elastic material - 4. (Fig. 4) is placed (put on) on the primary crown -2 (Fig. 4). Next, excess elastic plastic is removed, polymerization is completed (from 4 to 10 minutes, depending on the material) and the outer crown with elastic material is removed from the inner crown. Thus, we obtain an elastic retainer exactly corresponding to the inner crown - 4 (Fig. 4).

By applying an external crown with an elastic retainer to an internal crown, frictional force will be provided between the internal crown and the elastic material on the internal surface of the external crown, which ensures uniform friction and optimal bonding force. In addition, the formed circular ledge in the region of the edge of the secondary crown provides protection of the elastic intercoronal fixator from “seizures”, thereby prolonging its service life.

When using the proposed device for fixing a removable denture, the intercrown fixator can be considered as an element of additional fixation and stabilization of the removable denture. When docking the inner and outer crowns, pressure is created from the elastic material on the supporting surface of the inner crown. Thus, the telescopic system with the proposed intercoronal fixator provides good mechanical fixation of the removable denture. It is possible to replace the latch when worn. For better retention of telescopic crowns among themselves, and hence the removable prosthesis on the crown, you can use a smaller thickness of the elastic retainer layer, taking into account the compliance of the mucous membrane of the edentulous area of the prosthetic bed within 0.2-0.3 mm. Usually in practice, the compliance of the mucous membrane under a removable prosthesis is within these limits.

Clinical example of the application of the proposed utility model

Patient K., 59 years old, came to the clinic with complaints of missing teeth and difficulty chewing food (Fig. 5).

Objectively: the patient has a partial absence of teeth in the upper and lower jaws (Class 1 according to Kennedy). Teeth 1.1., 2.2. of the upper jaw have mobility of the 3rd degree according to Antin. Teeth 3.3., 4.3., 4.4., 4.5. motionless.

Treatment plan: extraction of teeth 1.1., 2.2. of the upper jaw and the manufacture of a complete removable lamellar denture for the upper jaw and the manufacture of an overlapping removable denture for the lower jaw supported by teeth 3.3., 4.3., 4.4., 4.5. with our proposed device for fixing a removable denture.

After preliminary therapeutic preparation of the teeth of the lower jaw (treatment of caries, pulp devitalization), the teeth were prepared for primary crowns and impressions were taken from the upper and lower jaws. In the dental laboratory, primary cast metal crowns - 2 were made on the stump of the teeth of the lower jaw (Fig. 6).

Cast external crowns were made according to the internal crowns and fixed in the base of the removable prosthesis. After that, the inner part of the outer crowns (3) was selected with an abrasive tool 0.4 mm thick with the creation of a circular ledge, processed using a sandblaster, adhesive was applied, the outer crowns (3) were filled with cold polymerization plastic and placed (put on) on the inner crowns ( 2). After removal of excess plastic and final polymerization, the prosthesis with external crowns was removed from the internal crowns (Fig. 7).

The internal crowns were fixed in the oral cavity on glass ionomer cement (Fig. 8), after which the finished removable prosthesis with external crowns was applied to the lower jaw with internal cast crowns (Fig. 9).

The proposed device for fixing a removable denture was used in 22 patients. Patients were observed after prosthetics for 2 years. The treatment results are good.

Claims (1)

A device for fixing a removable denture, containing an inner, an outer crown and an intercrown retainer, characterized in that the intercrown retainer is made of an elastic elastic material and is placed along the entire inner surface of the outer crown, not reaching 2 mm to its edge, and the thickness of the elastic material in the non-working position is 0.4 mm, and a circular ledge is formed on the edge of the outer crown to protect the elastic retainer of the outer crown, which can be attached to the base of the removable denture.