Cytotoxicity and genotoxicity of natural resin-based experimental endodontic sealers.

OBJECTIVES: The development of endodontic sealers based on natural resins seems to be promising, given their improved biological properties. This study evaluated the cytotoxic and genotoxic effects of two experimental root canal sealers, based on extracts from Copaifera multijuga and Ricinus communis (castor oil polymer), comparing them to synthetic resin-based sealers: a single methacrylate-based, a multi-methacrylate-based, and an epoxy resin-based sealers. MATERIALS AND METHODS: Sealers were prepared, set, and exposed to cell culture medium for 24 h at 37 °C with CO2. V79 cells were exposed to serial dilutions of the extracts of each sealer for 24 h. Cell viability was measured by the MTT assay and genotoxicity was assessed by the formation of micronuclei. RESULTS: The single methacrylate-based sealer had the most cytotoxic effects, with significant reduction in cell viability in all dilutions of the extract. The castor oil polymer-based sealer was, on the other hand, the most biocompatible sealer, with no cytotoxic effects at any concentration. All tested sealers were not genotoxic, excepting the single methacrylate-based sealer. CONCLUSIONS: The tested natural resin-based sealers presented low cytotoxic and no genotoxic effects on cell cultures. CLINICAL RELEVANCE: These results may suggest a good alternative to develop new endodontic sealers, in order to achieve better biological response and healing, when compared to commercially available sealers.

Cytotoxicity and genotoxicity of root canal sealers based on mineral trioxide aggregate.

INTRODUCTION: MTA has good biological properties, and it is a mineralization-inducing material with different indications in endodontics. Initially this material was not recommended as root canal sealer. However, a resin sealer based on mineral trioxide aggregate (MTA Fillapex) was recently released with this indication. Because MTA is in contact with the periodontal tissues, bone, and pulp, it is important to know its cytotoxic and genotoxic effects. The purpose of this study was to evaluate the cytotoxicity and genotoxicity of MTA canal sealer (Fillapex) compared with white MTA cement and AH Plus. METHODS: Chinese hamster fibroblasts (V79) were placed in contact with different dilutions of culture media previously exposed to such materials. Cytotoxicity was evaluated by methol-thiazol-diphenyl tetrazolium assay in spectrophotometer to check the viability rate and cell survival. The genotoxicity was accessed by the micronucleus formation assay. Cell survival rate and micronuclei number were assessed before and after exposure to cement extracts, and the results were statistically analyzed by Kruskal-Wallis and Dunn tests (P < .05). RESULTS: The results showed that the cell viability remained above 50% in white MTA group for all dilutions. AH Plus induced an intermediate cytotoxicity in a dilution-dependent manner, followed by Fillapex MTA. CONCLUSIONS: White MTA group was the less cytotoxic material in this study. Both AH Plus and Fillapex MTA sealer showed the lowest cell viability rates and caused an increased micronucleus formation when compared with control untreated group.