Dental impression materials

Dental impression materials (impression materials) are mixtures of various substances used in dentistry for obtaining the cast (print) with the dentition for subsequent casting models, which produce a denture.
The domestic industry produces dental impression materials three groups.
1. Solid dental impression materials (harden in the mouth): a) the gypsum used in prosthetic dentistry at all kinds of prosthetics; removal of plaster casts from the mouth of his break, then collect the fragments of the cast and stick together; the main disadvantages of gypsum are difficult to derive from the mouth, blurring of saliva; b) dental - consists of oxide of zinc and eugenol with fillers; used to obtain copies of the edentulous jaw.
2. Elastic dental impression materials applied in all kinds of prosthetics. Casts from elastic materials are easily removed from the mouth, are not washed away with saliva, give an exact image of prosthetic field. These are multicomponent mass and composition are divided into: a) alginate impression materials - stomalogy, Ivolgin, angelost; their bottom is alginat sodium; used for obtaining copies of partial defects of dentitions; lack of these masses is a large shrinkage mould of long storage in the air, in order to avoid this it is recommended to cast model immediately after removing mold from the mouth; b) silicone and) tikalova (Seelust and tident). Part silicone masses is based on silicone polymers, tiolovykh - multifunctional mercaptans. These two groups Cm. most accurately convey the structure of the surface of the mucous membrane of the mouth and teeth; casts easily deduced from the mouth and no shrinkage during prolonged storage. Use them for prosthetics toothless jaws and upon receipt of the copies of individual teeth when microprosthesis.
3. Thermoplastic dental impression material is softened and harden as a result of increasing and decreasing temperature. The domestic industry produces them under the numbers 1, 2. 3. Thermoplastic dental impression materials of the first two rooms used for the removal of the subsidiary cast and casts toothless jaw; 3 - for the removal of casts in the manufacture of polyuronic and tabs. Thermoplastic dental impression materials after sterilization can be recycled.
Modelling materials used in dentistry for modeling elements prostheses; in the manufacture of prostheses these materials are replaced by metal or plastic. The basis of modelling materials are compositions of different waxes, pigments and other components. In modelling the materials used for the simulation of the bases of prostheses and bridges, the basis is paraffin wax and beeswax in different proportions. In solid modelling wax, used for simulation of helical teeth, plastic crowns and inlays, except wax and beeswax, include Carnauba wax, raising the melting point of this wax compositions.