Tissue reactions after subcutaneous and intraosseous implantation of mineral trioxide aggregate and ethoxybenzoic acid cement

Biocompatibility of mineral trioxide aggregate and ethoxybenzoic acid cement was investigated by subcutaneous and intraosseous implantation of the materials in rats. Tissue reactions were studied at 15, 30, and 60 days after implantation. Subcutaneous implantation of mineral trioxide aggregate initially elicited severe reactions with coagulation necrosis and dystrophic calcification; the reactions, however, subsided to mostly moderate with time. Subcutaneous implantation of ethoxybenzoic acid cement initially elicited mostly moderate reactions that subsided to mild in time. Osteogenesis was not observed with either material upon subcutaneous implantation indicating that neither material is osteoinductive. Reactions to intraosseous implants of both materials were less intense than with subcutaneous implantation. Osteogenesis occurred in association with intraosseous implants indicating that both materials are osteoconductive. © 2000 John Wiley & Sons, Inc. J Biomed Mater Res, 52, 528–533, 2000.