ETHYLENE-OXIDE GAS STERILIZATION DOES NOT REDUCE THE OSTEOINDUCTIVE POTENTIAL OF DEMINERALIZED BONE IN RATS

It has been shown that different sterilization procedures of demineral ized bone may influence its osteoinductive properties. The aim of this study was to evaluate the effect of ethylene oxide sterilization for 1, 3, and 6 hours on the osteoinductive potential of allogeneic demine ralized bone implanted heterotopically in rats. Sixty male Wistar rats were randomly assigned to one of four groups, A through D, and four d emineralized bone chips (2.8 mg) were implanted in a pouch created bet ween the right oblique abdominal muscles in each animal. In Group A, t he demineralized bone was implanted without prior sterilization of the material, whereas the demineralized bone implanted in Groups B, C, an d D had been sterilized in ethylene oxide gas for 1, 3, or 6 hours, re spectively, and aerated for 48 hours. At 4 weeks postoperatively, bone formation was evaluated quantitatively by strontium 85 uptake and qua litatively by light microscopy of histological sections. One-way analy ses of variance at the 0.05 level revealed no significant difference i n strontium 85 uptake of the different groups, and no qualitative diff erences in osteoinduction could be detected by light microscopy. Ossic les consisting of bone and bone marrow were seen in the recovered impl ants of all groups.