Genotoxicity of three endodontic sealers by single cell gel-electrophoresis/comet assay

Introduction: The aim of this study was to compare the genotoxicity of two MTA-based sealers (MTA Fillapex and MTA Plus) and a RealSeal self etch (SE) sealer. Methods: Twenty discs of each sealer were constructed, dissolved in cell culture media and sealer extracts were diluted into two different concentrations 100% and 50%. Thereafter Baby Hamster kidney fibroblast cell cultures were treated with each concentration of tested sealers for two exposure periods 24 h and 5 days. Comet assay was used to evaluate DNA damage by measuring tail length and intensity, and the results were statistically analyzed by Kruskal-Wallis and Mann-Whitney U tests (P ≤ 0.05). Results: After 24 h, 100% medium extracts of RealSeal SE showed significantly the highest DNA damage followed by MTA Fillapex. After 5 days, MTA plus induced the least DNA damage at both tested concentrations. The DNA damage of both RealSeal SE and MTA Fillapex was significantly dose and time dependant. Conclusions: MTA Plus was the least genotoxic sealer in this study and its genotoxicity is not significantly affected by exposure time or its concentration.