小下颌畸形矫治术后的生物力学研究

The Experimental Mechanics Study after Sagittal Split of Ramus Mandible Osteotomy of Micrognathia

通过猴下颌升支矢状骨劈开前徙术（ＳＳＲＯ）后骨愈合区的生物力学研究发现，术后骨愈合区的组织属于各向异性材料，在不同的方向上加载，显示出不同的力学性能。在拉、压、弯、剪四种载荷中，骨愈合区的抗剪切能力恢复最慢。术后第６周，骨愈合区的主要力学性能基本恢复，提示该时期可作为临床正颌术后的颌间固定期限，此后病人可以在生理应力范围内进行训练，以促进骨的修复重建。实验证明，骨的修复重建过程是依据功能适应性原理，在力学状态控制下骨的生长和吸收的过程，而不是干扰和破坏骨应承受的力学状态。

After sagittal split ramus osteotomy mandiblar advancement, the bone tissue of the healing area belong to anisotropic material wihch demonstrates different direction loads In each group the scab resistance ability to shearing stress was the weakest compared with three kinds of other loads (pressure, strain, flexability) Scabs can recover the basic mechanic strength in 6 postoperative weeks, that means the 6th week may be used as the limited time for the maxillomandibular fixation in orthognathia clinical work At this time, patients can begin to train for reconstitution and reparative of bone structure The process of repair is controlled by a mechanical situation