Cytotoxicity and proliferative effects of Iodoform-containing root canal-filling material on RAW 264.7 macrophage and RKO epithelial cell lines

Objective: The present study investigated the effect of the Iodoform-containing root canal filling material on the viability of cultured macrophages and epithelial cells, and on cytokine secretion. Design: The effect of Endoflas F.S. on the proliferation of a RAW 264.7 macrophage cell line and on a RKO epithelial cell line, and on the production of tumour necrosis factor alpha (TNFα) from macrophages was examined. Cell vitality was evaluated using a colourimetric XTT (sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5- [(phenylamino)-carbonyl]-2H-tetrazolium inner salt) assay. The presence of cytokines was determined by two-site enzyme-linked immunosorbent assay (ELISA). Results: Direct exposure of Endoflas F.S. and its media, up to a dilution of 1/8, decreased the viability of macrophages and epithelial cells by ∼70% compared to control media (P < 0.05). Media dilution from 1/16 to 1/1024 demonstrated a proliferative effect, increasing cell viability by about 60% compared to media without Iodoform-containing root canal filling material. Conclusions: Direct and indirect exposure to high concentrations of iodoform-containing root canal filling material showed a cytotoxic effect on macrophages and epithelial cells, while low concentrations induced cell proliferation.