Comparison of bone formation ingrafted periosteum harvested from tibia and calvaria.

Periosteum covers the bone surface and displays the potential to initiate bone formation, after injury to the bone. Numerous studies have demonstrated that the periosteum plays major roles in the healing process after bone fracture. Some reports have described that in the healing of long bone fractures, the periosteum forms new bone by intramembranous and endochondral ossification. Other researchers insist that healing of defects in membrane bone shows bone formation by intramembranous ossification. However, previous studies have not been able to clarify differences in bone formation patterns. We hypothesized that differences in bone formation pattern are associated with the periosteal potential for cell differentiation. The present study grafted periosteum, harvested from the tibia and calvaria, into the suprahyoid muscle, with the aim of interrupting release of factors from bone matrix. Bone formation, after grafting periosteum, harvested from the tibia and calvaria, was examined histologically and radiographically. Grafted tibial periosteum formed a large area of new bone by intramembranous and endochondral ossification, while grafted calvarial periosteum displayed intramembranous ossification. Grafted tibial periosteum formed a larger area of bone than grafted calvarial periosteum. Patterns of cell differentiation thus differ between grafted periosteum, harvested from the tibia and calvaria.