Mineral trioxide aggregate (MTA) is a biocompatible endodontic retrofilling material. A recently developed calcium silicate (CS) cement has also shown similar physical and chemical properties as MTA. The purpose of the present study was to compare the biocompatibility of MTA and CS with mouse fibroblast (L929) cell line. MTA cements and 4 CS cement group made of different components were cultured with L929 for 1, 3, 7 and 15 days. L929 cell survival rate was measured by mitochondria colorimetric assay (MTT), the morphology of the cells growing on the cements were observed by scan electromicroscope, and the expression ERk and pERk L929 cell measured by Western blot analysis. One way analysis of variance (ANOVA) was used to determine statistical difference. A p<0.05 was considered significant. Both MTA and CS cement were found to be equally biocompatible with L929 cells. L929 cell attached well to both MTA and CS cements. The L929 expression of ERk and pERk was the same for both groups. We conclude that CS and MTA share the same biologic properties and are equally biocompatible with L929 cells.
