|Budget Amount *help
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1995: ¥200,000 (Direct Cost: ¥200,000)
Fiscal Year 1994: ¥200,000 (Direct Cost: ¥200,000)
Fiscal Year 1993: ¥1,700,000 (Direct Cost: ¥1,700,000)
A sintered bone had the lowest antigenicity among a variety of allogeneic preserved bones, followed by autoclaved, demineralized, lyophilized, frozen, partially demineralized, and defatted bones.
When combined with rat allogeneic preserved bone and bovine bone morphogenefic protein (BMP) augmented bone substitute, demineralized and lyophilized bones were the most excellent in osteoinductivity and biomechanical strength, respectively.
In a defect after marginal mandibulectomy, the implants described above with bone marrow induced more bone formation than they alone. Combination with bone marrow resulted in no significant differences in osteogenesis between demineralized and lyophilized bones. In biomechanical strength, however, the lyophilized bone had superior results regardless combination with bone marrow. There were no significants differences in responses of surrounding soft-tissues on implants among experimental groups.
In implantation into a mandibular segmental defect, the unstability of implant materials prevents the experiment from progressing. Moreover, the result from the rat experiment seems difficult to suggest a possibility of clinical applications. Therefore, it is necessary to perform the same experiments using a rabbit, dog or monkey, and we are now in progress.