【摘要】 目的 :探讨下颌升支矢状骨劈开术 (SSRO)前徙下颌后 ,在不同颌周肌肉作用下 ,下颌升支手术区内的应力分布情况 ,从理论力学的角度为临床治疗提供依据。方法 :利用建立的下颌骨三维有限元模型 ,研究不同载荷作用下的应力分布 ,并与正常对照分析。结果 :下颌升支矢状骨劈开前徙下颌后 ,不同颌周肌力作用时 ,骨愈合部位大应力区的分布状况不一样 ,下颌角和下颌升支后份为应力集中的区域。结论 :正常情况下的应力对于骨折愈合区可能是骨段固位不稳定的主要因素 ;SSRO后 ,近远中骨段的固定位置应选择在能使下颌升支应力分散的区域 ,至少应保持 6～ 8周。更多还原

【Abstract】 Objective: To study the distribution of stress caused by different mastication muscles in mandibular ramus operative area after sagittal split ramus osteotomy (SSRO), so as to guide the clinical work. Methods: The stress distribution under different loads in the center of element model was studied by means of a three-dimensional finite element computer model which was constructed with data from normal human being, and contrastive analysis was made with the data of normal. Results: After SSRO, under the effects of different peripheral muscles, the stress distribution in the union area was different. The mandibular angle and the posterior portion of the ramus were the areas baring high tension strains. Conclusions: Under normal physiological conditions, the stress on the union area might be the main cause that makes segment fixation unstable. After SSRO, the fixation point should be placed in those areas that the stress to mandibular ramus can be dispersed, and the fixing duration should be 6 to 8 weeks at least.更多还原