Endodontic cements induce alterations in the cell cycle of in vitro cultured osteoblasts

The effects of endodontic cements on the cell cycle of MG63 osteoblasts cultured in vitro have been examined. Three groups of compounds were tested. Group I encompassed zinc oxide- and eugenol-based cements (Tubliseal, Argoseal, N2), group II consisted of cements with a phenol group other than eugenol (AH26, Forfenan, Methode R/R), and group III included CaOH-based cements (Biocalex, Endocalex). The cell cycle of MG63 cells was analyzed by flow cytometry; the DNA content was evaluated by means of the propidium iodide uptake method, whereas the proportion of cells in the S phase was defined by the incorporation of bromodeoxyuridine later revealed by a specific antibody. The results showed that some root canal sealers could hamper the periapex healing processes by inhibiting the cell proliferation through a selective action on different phases of the cell cycle.