Cytotoxicity of mineral trioxide aggregate using human periodontal ligament fibroblasts.

The purpose of the present study was to compare the cytotoxicity of mineral trioxide aggregate (MTA) to other commonly used retrofilling materials, Super-EBA and amalgam. This was accomplished using a cell viability assay for mitochondrial dehydrogenase activity in human periodontal ligament fibroblasts after 24-hr exposure to extracts of varying concentrations of the test materials, in both freshly mixed and 24-hr set states. Methyl methacrylate 2% (vol/vol) served as the positive control, and complete culture medium served as the negative control. Differences in mean cell viability values were assessed by ANOVA (p < 0.05). In the freshly mixed state, the sequence of toxicity was amalgam > Super-EBA > MTA. In the 24-hr set state the sequence of toxicity at a low extract concentration was Super-EBA > MTA, amalgam, and Super-EBA > amalgam > MTA at a higher extract concentration. This study supports the use of MTA in the root-end environment.