两、三焦点牵张成骨在下颌骨缺损修复中的应用

目的：通过两焦点、三焦点对山羊下颌骨缺损进行牵张,比较两种牵张成骨方式的新骨成骨量。方法：将8只成年山羊随机分成两组,每组4只,分别采用两焦点和三焦点牵张成骨术进行骨缺损修复。牵张结束后固定8周,处死动物取牵张区新生骨组织标本进行X线检查、组织学检查、骨密度分析。结果：两实验组牵张区新骨生长的质无明显区别,在量的比较上,三焦点组X线检查、组织学检查、骨密度测定的结果均好于两焦点组,骨密度测定分析结果有统计学意义（P〈0.05）。结论：三焦点牵张成骨在大面积颌骨缺损的修复中新骨的成骨量好于两焦点牵张成骨组。

Application of bifocal distraction osteogenesis and trifocal distraction osteogenesis for reconstruction of mandibular defect

Objective：To compare（bifocal distraction osteogenesis and trifocal distraction osteogenesis） in goat mandibular defectt,o explore the new bone mass of distraction osteogenesis in the treatment of mandibular defect.Method：8 adult goats were randomly divided into bifocal distraction group（n=4）and trifocal distraction group（n=4.） killed at the 8 weeks after completion of distraction and corresponding time in two group.Gross X-Ray,histological and bone densitometry were performed to evaluate the state of the bone healing and regeneration.Result：The newly generated bone substance no obviously difference in distraction gap,but newly generated bone quantitative trifocal distraction to compare bifocal distraction,Gross X-Ray,histological.Trifocal distraction bonedensitometry in remarkably higher than that in bifocal distraction（P 0.05）.Conclusion：The technique of trifocation distraction is better than that of bifocal distraction in a large area mandibular defect.