Method: Materials were prepared according to the manufacturers’ instructions and then were immersed in medium and left to elute for 24h, 48h, 72h and 5 days. 3T3 fibroblasts were exposed to different dilutions of the extracts for 24h. Cell viability was measured using two different assays (MTT and Crystal Violet).
Result: The 24h eluate of urethan dimethacrylate-based resin is more toxic than bis-acryl and methyl methacrylate-based resins. This effect is directly proportional to the amount of extract added. The highest concentration of urethan dimethacrylate-based resin causes significant cytotoxicity in our cell model (only 20% of cell viability, p<0,001). For this resin, the elution time does not seem to increase the toxicity. However, bis-acryl based resin does not show substantial effect at 24h of elution, but after 48h of elution cell viability decreases.
Conclusion: Our study indicates that provisional restoration materials have cytotoxic effects on fibroblasts; in particular, the urethan dimethcrylate based resin. In some cases chemical stability of the materials might be altered with time. Specifically, 24h eluate of bis-acryl based resin does not show significant cytotoxicity, however, cell viability decreases with longer incubation times. The cytotoxicity of this material also depends on the exposition time.