ABSTRACT
For many years various soft materials have been used to line prostheses in order to eliminate irritating effect of prosthesis on the prosthetic base. Different materials have been used for this reason: soft acryl, acryl-silicone materials, and for some time, more and more often, silicone elastomers [15]. These latter materials are basis for investigation of physical mechanical and physical chemical properties [6]. One of the physical mechanical investigations in case of elastomers is examination of the tensile strength. It should be explained that the tensile strength of a silicone elastomer exerts a decisive effect on the intramolecular forces, which prevent movement of molecules in relation to each other, and the force of chemical bonds [7]. The tensile strength, calculated on the basis of interatomic and intermolecular forces, is not comparable with the tensile strength calculated in practice. The differences can be explained by heterogeneities – microdefects in the material, i.e., structural discontinuities. They cause concentration of applied tensions primarily on the borders. The originating defect may initiate spacing, cracking and rupture of the sample.
