In vitro toxicity of propolis in comparison with other primary teeth pulpotomy agents on human fibroblasts

Aim: The aim of this study was to assess and compare the in vitro toxicity of propolis with other primary teeth pulpotomy medicaments. Methods: Human periodontal ligament (PDL) cells were subjected to different concentrations of propolis, formocresol, ferric sulfate, and gray mineral trioxide aggregate (MTA) (0.05, 0.5, 5, 50, and 100 mu g/mL) for 24 h at 37 degrees C. Cells that were not exposed to the tested materials served as the negative control. In vitro toxicity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Statistical analysis of the data was accomplished using ANOVA and Tukey statistical tests (P < 0.05). Results: Only propolis and gray MTA had comparable cell viability to the negative control group. Almost all remaining concentrations of tested materials were significantly inferior to the negative control after 24 h of exposure (P < 0.05). Conclusion: Propolis and MTA are more biocompatible than formocresol and ferric sulfate since they were both able to preserve PDL fibroblasts for up to 24 h.