New Bone Formation Process Using Bio-Oss and Collagen Membrane for Rat Calvarial Bone Defect: Histological Observation.

PURPOSE: We carried out guided bone regeneration of cranial bone defects in rats using the bovine bone substitute Bio-Oss and a collagen membrane and performed histological observations of the bone repair process. MATERIALS AND METHODS: Bone defects were created in the cranial bones of 30 15-week-old Sprague-Dawley rats. We made 3 groups. A is unfilled, B is Bio-Oss, and C is Bio-Oss plus a collagen membrane. At 4 or 8 weeks postoperatively, tissue samples were taken. The Kawamoto technique was used for histological evaluation. RESULTS: There was no new bone formation in group A. In groups B and C, new bone formation was evident around the Bio-Oss. In group C, new bone formation was evident in the centers of the bone defects, detached from the cut edge of the cranial bone. CONCLUSION: Our results suggested that the Bio-Oss acts as a scaffold for bone repair, and the use of a collagen membrane may anchor the Bio-Oss closely to the cranial bone and assist the bone repair response.