Development of a Technique Promoting Ossification in the Distraction Osteogenesis

点击翻译按钮获取中文摘要

The distraction osteogenesis is a useful and reliable technique for bone regeneration. However, the distraction technique needs long period for bone formation in the distraction zone. In this study, in order to improve this disadvantage of the distraction technique, we tried to identify various growth factors expressed in the distraction zone and apply these growth factors to the distraction zone to promote bone formation. We used a distraction model in the rabbit mandible established in our laboratory. In addition, we tried to establish this kind of distraction model in the dog mandible and expand the experimental animal into monkey. However, in the present stage, we perform experiments of the mandibular distraction in rabbits because of its reproducibility. In the rabbit experiment, mRNAs of some kinds of growth factors were expressed in the distraction zone. However, we could not completely identify these growth factors. On the other hand, bone morphogenetic protein (BMP) promoted bone formation in the distraction zone of the rabbit mandible and its administration was more effective on the last day than on the first day of distraction. Now, we try to examine a similar experiment using other growth factors except BMP. Moreover, we observed the histological difference in the soft tissue (muscle and mucous membrane) surrounding mandible between in distraction osteogenesis and one-stage bone extension. When we examined the soft tissue surrounding mandible immunohistologically, tissue regeneration was more active in the distraction osteogenesis than in the one-stage bone extension. The distraction osteogenesis is said to be distraction histiogenesis. We believe that elucidation of the distraction histiogenesis in the soft tissue is also an important theme regarding distraction osteogenesis.