Cytotoxicity of RealSeal on Human Osteoblast-like MG63 Cells

Introduction: The purpose of this study was to compare the cytotoxicity of a new root canal filling material (RealSeal .system) with epoxy resin based root canal sealer (AH Plus) and gutta-percha by using human osteoblast-like MG63 cells. Methods: Samples of each test material were fabricated in sterile cylindrical Teflon tubes of 4.4 mm diameter and 2 mm height. Extraction of specimens was carried out after setting in cell culture medium by using the ratio of 1.25 cm(2)/mL according to ISO 10993-5. Cytotoxicity was assessed by direct incubation of different extracts with MG63 cells at different time intervals. The dimethylthiazol diphenyltetrazolium bromide assay and flow cytometry were used to test the proliferation of MG63 cells. The results were analyzed with a Tukey test (alpha = 0.05). Results: The gutta-percha was nontoxic to MG63 cells in vitro, whereas RealSeal core material showed initial cytotoxic effect on MG63 cells after 1 day of culture, which disappeared after 3 days of culture. The RealSeal sealer was significantly more cytotoxic than AH Plus (P < .05) within 3 days. Flow cytometry showed that cell proliferation in RealSeal sealer and AH Plus group was inhibited. Conclusions: The RealSeal sealer was significantly more toxic to MG63 cells than the AH Plus within 3 days, whereas RealSeal core material was similar with gutta-percha. Further research is required to evaluate the biocompatibility of RealSeal system comprehensively. (J Endod 2010;36:40-44)