Assessment of the genotoxicity of resin and zinc-oxide eugenol-based root canal sealers using an in vitro mammalian test system

Endodontic sealers frequently are placed in direct contact with living tissues. Thus root canal sealers should have good biocompatibility. However, the pathobiologic effects, especially genotoxicity, of various root canal sealers widely used in dentistry have not been studied systematically on eukaryotic cells. The aim of this study was to examine the genotoxic potential of resin and zinc oxide-eugenol-based root canal sealers using a mammalian test system. In this study, tetrazolium bromide reduction assay, DNA precipitation assay, and DNA fragmentation analysis were performed to investigate the cytotoxic and genotoxic effects of four different root canal sealers on cultured V79 cells. The results show that all the root canal sealers tested are cytotoxic to V79 cells. The toxicity decreased in the order of N2 > AH26 > AHplus > Canals. In addition, N2, AH26, and AHplus exhibited genotoxicity by causing DNA single-strand breaks and digestion of genomic DNA. However, N2 is the most toxic root canal sealer among those tested. Taken together, these findings suggest that the sealers evaluated in this study show different toxic effects depending on the types and components. Root canal sealers containing formaldehyde and bisphenol A diglyether proved to be not only cytotoxic but also genotoxic. This mammalian test system might be used routinely for evaluation of the genotoxicity of dental materials in future investigations.