[Comparative study on the biological properties of plastics for temporary crowns and bridges].

Six different plastic materials for temporary crowns and bridges were tested comparatively concerning their biological properties. To this the temperature in the pulp cavity was measured in vitro while making temporary crowns. Also the cytotoxicity was determined by the hemolysis-test. The results obtained showed that there is no thermal irritation of the pulp if the temporary plastic material is applied in an alginate impression as usual in practice. Cytotoxicity of the hardened plastics was not provable. Nevertheless tissue irritation can not be justified when using polymethacrylates and epimine-resin.