Influence of polymerization method on the cytotoxicity of three different denture base acrylic resins polymerized in different methods
Zbigniew Raszewski
Abstract
STATEMENT OF PROBLEM: Acrylic plastics are used for over 80 years for the manufacture of prostheses. This kind of material has some limitations, one of them is a residual monomer, that remains after the polymerization has been terminated, which can influence the biological properties of the final medical device. THE PURPOSE: The aim of this investigations was a comparison of the residual monomer concentration and cytotoxic effect of three various acrylic materials which differ in the polymerization method (hot-cured, polymerized under pressure and at lower temperatures). MATERIAL AND METHODS: The cytotoxicity of three different acrylic resins from the same producer were tested on the in vitro model (VERO CCL-81) by MTT assay. The residual monomer of acrylic materials was detected by gas chromatography. RESULTS: The Superacryl Plus material polymerized in hot water has a residual monomer concentration of 0.67 ± 0.05%, Superpont C + B hardened under pressure of 2.61 ± 0.208%, and Premacryl Plus after cold curing process has 3.53 ± 0.27% of uncured MMA. The results revealed that the least cytotoxic effect were observed in case of a thermally polymerized material. CONCLUSION: Material polymerized in high temperatures has lower residual monomer concentration and not affect cell cultures. Self-curing materials polymerized in lower temperature have a higher concentration of residual monomer, which reduces the number of living cells by 20%, which can cause allergic reaction shortly after new denture was prepared.