Ex vivo cytotoxicity of a new calcium silicate-based canal filling material

P>Aim To evaluate the biocompatibility of iRoot SP root canal filling material to L929 mouse fibroblasts. Methodology Specimens of iRoot SP, AH Plus and ProRoot mineral trioxide aggregate (MTA) were prepared for direct contact using the Millipore filter diffusion test, as well as extracts in MTT assay. Mouse fibroblasts (L929) were used as toxicity targets. Differences in cytotoxicity between fresh and set specimens and between root canal material extracts were determined by t-test. A P-value < 0.05 was considered statistically significant. Results In the filter diffusion test, iRoot SP was slightly cytotoxic when tested as a fresh mixture and not cytotoxic in a set condition tested after 24 h. AH Plus was rated moderately cytotoxic when tested as a fresh mixture and slightly cytotoxic in a set (24 h) condition. MTA was noncytotoxic in both a fresh or set state. AH Plus was significantly more toxic than iRoot SP and MTA (P < 0.05). In addition, iRoot SP was significantly more toxic than MTA (P < 0.05). In the MTT assay with set specimens, extracts of iRoot SP and MTA were noncytotoxic, whilst extracts of AH Plus were rated as slightly cytotoxic. AH Plus was significantly more toxic than iRoot SP and MTA (P < 0.05). Conclusion AH Plus root canal sealer was significantly more toxic to L-929 cells than MTA and iRoot SP. iRoot SP had intermediate toxicity.