METHOD OF DETERMINING STRENGTH OF DENTAL MATERIAL CONNECTION FOR FIXATION WITH HARD TOOTH TISSUES AND NON-REMOVABLE DENTAL PROSTHESIS MATERIAL AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2021 - IPC A61C5/00 

FIELD: dental material science.

SUBSTANCE: method for determining strength of connection of dental material for fixation with hard tooth tissues and structural material of fixed dentures involves preparation of substrate samples from hard tooth tissues or from structural material of prosthesis, preparation of specimens of adhesive bonding and carrying out of test for shift by means of Instron testing machine at speed of movement of cross-beam of 5 mm/min till complete destruction of glued sample; adhesion strength of connection is determined by formula: A_sd=F_sd/S, where F_sd is the limit load at which the sample compound is destroyed, N; S is area of surface, over which destruction takes place, mm. Note here that appliance consisting of upper and lower parts is used, each of which is fixed in appropriate clamp of Instron testing machine. Prior to installation of upper part into upper clamp of testing machine sample adhesive bond substrate is fixed with two screw clamps in hole of upper part of appliance made in form of plate. Load on test material is applied by rounded end of lower part of appliance, made in form of elongated plate, opposite end of which is fixed in lower clamp of testing machine. A sample of a substrate of a fixed non-removable dental prosthesis of alloy or stainless steel or zirconium dioxide is prepared in the form of disc with diameter of 8 mm and thickness of 5 mm, and sample of substrate from composite material is prepared in the form of disc with diameter of 4 mm and thickness of 5 mm by layer-by-layer introduction of packable composite material intended for production of indirect composite restorations, followed by polymerisation. A sample of a dental tissue substrate is prepared by mounting a fragment of the removed tooth into a cylindrical mold filled with light curable mounting plastic, provided with a pusher, made with the possibility to move the pusher up and down and located in the lower position. After light hardening of the mounting plastic, the pusher is moved to the upper position; the substrate sample is extracted from the tooth hard tissues from the mold. A sample of an adhesive compound "test material – structural material of the prosthesis" or "hard tooth tissues – test material – structural material of the prosthesis" is prepared by applying load of 150±2 N for 15 minutes using a loading device.

EFFECT: higher measurement result reliability.

3 cl, 4 dwg, 6 ex