For many years, surgeons, bioengineers and related biomedical personnel have been striving to find a suitable material for the replacement of lost bone. Recently, Osteovit (purified collagen matrix of bovine origin, B. Braun, Melsungen AG) has been developed as a useful material for bone substitute. Implanted collagen material is absorbed itself by the enzymatic activity and phagocytosis of host tissue, and promotes the early ingrowth of vascularity and cell producing elements, and then induces the early healing of defects and new bone formation.
The present study was designed to inveatigate the effect of Osteovit on the osteogenesis at the calvarial bone defect and to compare the osteogenetic effect of Osteovit with that of control and autogenous bone graft groups.
In 25 rabbits, three full thickness bony defects measuring about 1 cm in diameter were made on the parietal bone of each rabbit and these bony defects were treated as followings and divided into three groups: 1) one hole as non-treated control group, 2) another hole as autogenous tibial bone grafted group and 3) the third hole as Osteovit treated group. Radiographic, macroscopic and histologic examinations were performed in 5 rabbits at 1, 2, 4, 8 and 12 weeks respectively after the operation.
The results were as follows;
1. The control group began osteoid formation at 2 weeks. The new bone formation and initiation of lamellation was found at 4 weeks. At 8 weeks, the bone defect site was replaced partially by calcified and lamellated new bone. And then newly formed bone was converted into thin trabecular bone at 12 weeks.
2. The bone regeneration in the autogenous bone graft group showed more rapid and better than that in control and Osteovit treated groups. The newly formed bone was mainly compsoed of thick compact bone, like the surrounding normal cortical bone at 12 weeks.
3. In the early stage of Osteovit treated group, the osteoid formation and calcification were not rapid in comparison with that of bone graft group. But in the late stage, the extensive formation of osteoid, calcification and lamellae could be observed as a result of progressive absorption of Osteovit and on significant difference was found in healing rate between the Osteovit treated and bone graft groups.
In summary, Osteovit promotes good bony regeneration comparable to autogenous bone graft when it is used in bone defect instead of bone graft, and can be used as a bone substitute.
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