Apoptosis and survivability of human dental pulp cells under exposure to Bis-GMA

OBJECTIVE: In the present study, we examined whether 2, 2-bis [4-(2-hydroxy-3methacryloxypropoxy) phenyl] propane (Bis-GMA) has effects on LSC2 cells, human dental pulp cell line. MATERIAL AND METHODS: The viability, cell cycle, and morphology of LSC2 cells were analyzed after exposure to several different concentrations of Bis-GMA. The recovery of viability of Bis-GMA exposed cells was also analyzed in the condition without Bis-GMA. Further, penetration of Bis-GMA to dentin disc was examined using isocratic high-performance liquid chromatography. RESULTS: There was a concentration-dependent decrease in cell proliferation and an increase in cell number in the sub-G1 population after exposure to Bis-GMA. Furthermore, the cells showed typical characteristics of apoptotic cells after the exposure to high concentration of Bis-GMA. In contrast, cells exposed to lower concentrations of Bis-GMA recovered their viability after being cultured without Bis-GMA. We also found that Bis-GMA is capable of penetrating 1-mm-thick dentin discs, though the penetrated concentration was lower than that showing cytotoxicity. CONCLUSION: These results suggest that Bis-GMA has cytotoxic effects, though dental pulp exposed to lower concentrations is able to recover their viability when Bis-GMA is removed.