Alterations in macrophages after exposure to root canal filling materials.

The process of engulfment of overextended root canal filling materials was investigated in rat peritoneal macrophages in vitro. Root canal filling materials tested were Finapec APC, Sealapex, Canals-N, and Canals. The phagocytosis rate of macrophages for the Finapec APC was significantly (p < 0.05) higher than that for other three root canal filling materials. That for Canals was the lowest. About 95% of the cells exposed to Finapec APC were viable at 60 and 120 min. For Canals the percentage was 74% and 63% at 60 and 120 min, respectively. Ruffle formation in macrophages was observed by scanning electron microscopy after exposure to Finapec APC for 60 or 120 min. Many vacuoles were observed in macrophages exposed to Canals for 60 min. It was concluded that the phagocytic rate of macrophages for Canals that showed a strong cytotoxicity was lowest and that the rate for Finapec APC that showed a low cytotoxicity was the highest.