Introduction: One of the most important characteristics of endodontic treatment seals is their biocompatibility. The aim of present study was to investigate the cytotoxicity of four types of freshly prepared root canal sealers using human gingival fibroblasts.

Materials and Methods: In this experimental laboratory study, freshly prepared sealers were investigated. To investigate the cytotoxicity, each sample was extracted separately in RPMI-1640 (Sigma Aldrich-USA). Then, the resulting extracts were exposed to C165 fibroblast cells in culture medium for 1, 3 and 7 days. Then, the level of cytotoxicity was assessed by MTT colorimetric method based on the level of light absorption. In the present study, multivariate analysis of variance was used to analyze the data.

Results: The results showed that the cytotoxicity of AH 26 and tgsealer sealers decreased and MTA Fillapex sealer increased over time. Also, Adseal sealer did not follow a logical trend but, in general, its cytotoxicity increased over time. In addition, based on mean of all data obtained from each sealer, MTA Fillapex had the lowest cytotoxicity and Adseal had the highest cytotoxicity, and AH 26 cytotoxicity was higher than that of tgsealer.

Conclusion: According to the results of the present study, the MTA-based sealer of MTA Fillapex has the lowest cytotoxicity.

Keywords: Root canal sealers, fibroblasts, freshly prepared roots