Histological comparison of bone induced from autogenously grafted periosteum with bone induced from autogenously grafted bone marrow in the rat calvarial defect model.

Both periosteum and bone marrow have the potential to induce heterotopic bone when grafted. Whether the process of bone formation is controlled by the recipient environment where the donor graft is placed or by factors from the donor site is not well documented. The purpose of this study was to examine the histology of new bone induced by either autogenously grafted periosteum or autogenously grafted bone marrow using the rat calvarial defect model in Sprague-Dawley rats. Grafts of either bone marrow or periosteum obtained from tibias were placed in calvarial defects with beta-tricalcium phosphate. Ten days after grafting, active cell proliferation was observed in the defects of both types of grafts. After 20 days, cancellous bone formation was observed in the defects with bone marrow grafts, and intramembranous bone formation was observed in the defects with periosteal grafts. After 30 days, bone marrow grafts had developed bone with a bone marrow-like structure, and the periosteal grafts had produced cortical bone structure in the defects. The findings suggest that the type of bone formation is determined by characteristics of the donor site.