The evaluation of bone formation of the whole-tissue periosteum transplantation in combination with beta-tricalcium phosphate (TCP).

We investigated the osteogenic potential of a combination graft of beta-tricalcium phosphate (TCP) and periosteum in the rat calvarial defect model. The combination beta-TCP and periosteum graft was grafted into rat calvarial defects; the newly formed bone in the defect was studied histologically and radiographically and compared with periosteum grafts and TCP grafts. Ten days after combination grafting, the grafted periosteum showed cell proliferation and Runx2 immunoreaction; 20 days after grafting, new bone formation was seen around the beta-TCP; and 30 days after grafting, new bone developed and actively replaced beta-TCP, while radiography showed calcified areas. Total bone formation of the combination periosteum and beta-TCP graft was significantly increased compared with single grafts of beta-TCP or periosteum (P < 0.01). The combination graft of periosteum and beta-TCP showed marked bone formation in rat calvarial defects. This result suggests that combination grafts may be effective for repairing bone defects.