CS264753B1 - Matrices for making proximal fillers from composite materials on premolars and molars - Google Patents

Abstract

Matrices for making proximal fillings on premolars and molars made of transparent plastic, eg polyvinyl chloride 0.04 to 0.06 mm thick, with a chewing surface.

Description

The present invention provides matrices for making proximal restorations of composite materials on premolars and molars. These matrices are of transparent plastic material and have a pre-chewing surface.

The proximal fillings on premolars and molars have so far been predominantly made of amalgam and are made using metallic materials, such as metal alloys, such as disclosed in DOS 3,220,621, where Memory Metal alloys are used. These alloys are described in Journal of Metals, 6, 1980, pp. 129-137. Also matrices of light metal alloys, e.g. aluminum alloys, are known. They are still shaped for teeth in the frontal section of the teeth.

Fillings on the proximal surfaces of premolars and molars are required to be mechanically resistant, have a good edge closure, and have a point of contact with the adjacent tooth so as not to change, shape and abrasion, to be X-ray contrasting and aesthetically pleasing. Although amalgam alloys largely meet these requirements, their disadvantage is their dark color; therefore, it is not suitable for patients who have an inley or gold alloy crown adjacent to the proximal caries. Also, patients who are publicly active or who work in theater, television and film, also require premolar and molar restorations that would also be aesthetically pleasing.

For these reasons, it is necessary to treat the proximal defects in the premolar and molar landscapes with a composite material.

Treatment of caries on the approximal surfaces of the teeth with a plastic filling also requires the use of matrices. Without their use, the fillings are overhanging, do not have the correct anatomical shape and often lack the point of contact with the adjacent tooth. These deficiencies can lead to periodontal damage, and this can also cause premature loss of the wrongly treated tooth after a long time.

Matrices used for amalgam fillers do not suit composite fillers. While the amalgam filler needs to be shaped, including the point of contact, only after the matrix has been removed, before the amalgam has hardened, the composite filler must be doped first and then the matrix can be removed. In such treated patients, the filler does not have a point of contact with the adjacent tooth, and the correct shape of the filler must often be ground after polymerization.

When grinding a conventional composite, the top layer, which mainly contains a binder, is removed. By grinding off this layer, the filler which is held by a silane bond in a conventional composite is exposed. It is not sufficiently resistant to the hydrolytic action of saliva. As the filler falls out, the filler surface coarsens and allows plaque retention with all the consequences.

A further disadvantage of the steel matrices used for conventional filler filler fillings that rub off the steel matrix of the matrix, and the filler along the matrix is therefore dark.

These drawbacks are solved by the invention which consists in the use of matrices made of transparent plastic, malleable after heating, for example of polyvinyl chloride 0.04 mm to 0.06 mm thick, optionally provided with preformed chewing surface, which can be preformed individually before use. The matrices are shown in Fig. 1 A, B.

Exemplary embodiment

Prior to caries preparation, a matrix of transparent material, in the form of a 0.06 mm thick polyvinyl chloride film, is clamped to the tooth by a matrix tensioner (eg Ivory 8). After clamping the die, the contact point is formed by the heated spherical stopper, thereby further weakening the die at the contact point. Thereafter, the chewing surface of the matrix is heated and pressed onto the tooth to shape the chewing surface of the matrix.

The matrix thus prepared is removed from the tooth and the carer prepares the caries. After the caries preparation, the matrix is again clamped to the tooth and the cavity is filled with composite. Then, the preformed chewing surface of the matrix is placed on the composite and the patient's crevices are formed into this part of the matrix by intercapital grooves. The extruded excess material is removed before the material is polymerized. After the polymerization of the material is complete, the matrix is removed and the filler is tested in a bite. The last excess material is discarded. The result is better fill and easier work.

Claims (1)

SUBJECT OF THE INVENTION A plastic matrix for making proximal fillings of composite materials on premolars and molars, characterized in that it is made of a transparent plastic, for example of polyvinyl chloride of thickness 0.04 to 0.06 mm, and is provided with a chewing surface.