Biomechanics is a branch of physics, which deals with the motion of bodies in space and arise in this process. Biomechanics studies the mechanical properties (hardness, density, elastic modulus, etc.) and mechanical phenomena, 5 of which must be applied in prosthetic dentistry. Dentists – clinicians – physicians and surgeons combine manual skills with drug treatment, and dentists – orthopedists, along with manual, non-drug use, machine tools, based on the data of physics, its sections, statics and kinematics, that is the biomechanics of prosthetic dentistry. Consequently, all kinds of contacts Teeth: superkontakty, primary and secondary occlusion, arthritis, arthritis, TMJ and pathological processes, etc. – all this biomechanical phenomenon. Each of the force acting on an inclined surface has a vertical and horizontal direction, so the normal reaction force (N) – perpendicular to the slope and the friction force (F), acting along the slope – are the first two parameters appearing in compression bolus (Fig.

1). On these components (N, F) should construct a parallelogram of forces, whose diagonal is Rn-bearing strength of the reaction (the third option of mechanical phenomena) – Figure 1. Rn occurs constantly in each chute at any contact of teeth. To assess the actions of all forces acting on the chewing surface of teeth, Taptunova (MSMSU) and Glasser (Germany) offered to take into account only 3 points on the slopes in the cross section of posterior teeth. Therefore, the 2-m in Fig. at points corresponding to contacts with the antagonists, are depicted P1, P2, P3. Each of these forces causes a reaction Rn1, Rn2, Rn3, perpendicular to the slopes (Fig.