The long-term survival of onlay bone grafts--a comparative study in mature and immature animals

Onlay bone grafting was studied with regard to age of the animal and type of bone graft used (membranous bone or endochondral bone with or without periosteum, and decalcified homograft). The bone grafts were placed in the nasal dorsum in a group of mature and immature New Zealand rabbits. Volume displacement studies were carried out. Graft survival was greatest in membranous bone and least in endochondral grafts. There was significantly greater absorption of endochondral grafts in immature animals than in the mature group. Presence or absence of periosteum did not make a significant difference in graft survival.