摘要： 目的： 建立下颌骨颏部节段性缺损弧形牵张成骨的三维有限元模型，研究弧形牵张成骨重建下颌骨颏部节断性缺损过程中，不断变化方向的牵张力对新骨组织形成的影响。方法： 建立颏部节段性缺损的三维有限元模型，并把简化后的弧形牵张器有限元模型置入截断后的下颌骨，模拟弧形牵张成骨，并测量在弧形牵张成骨过程中下颌骨整体位移及其von Mises应力分布。结果： 在未考虑唇颊侧软组织作用的前提下，弧形牵张成骨形成的新骨向舌侧生长，重建的下颌骨弧度较原下颌骨弧度变小。von Mises应力主要集中于牵张器在下颌骨的固位处。结论： 在弧形牵张成骨重建下颌骨缺损过程中，牵张力本身就促使新骨组织向舌侧生长，从而使重建的下颌骨弧度较正常时小。此项研究为临床上如何克服弧形牵张成骨所形成的下颌骨弧度较小的不足，提供了一定的理论依据。

关键词: 下颌骨缺损, 弧形, 牵张成骨, 重建, 有限元法

Abstract: Objective: The purpose of this study was to examine the  influences of  distractive forces by curvilinear distraction to the newly formed mandible through finite element (FE) method. Methods: A 3D mandibular bone midline region segment was modeled from computed tomography (CT) images of a human mandible, and  a 3D finite element model of a simplified simulated curvilinear distractor was recognized, then they were further fixed together. We analyzed the 3D bone-distraction model numerically to evaluate  von Mises stress distribution and newly bone formation. Results: The newly formed mandible deviated to the lingual side and the curvature of reconstructed human mandible was less than that of the normal. Von Mises stress concentration mainly occurred in the location of distractor in the mandible. Conclusion: In the process of reconstruction of human mandible segmental defects by curvilinear distraction osteogenesis, the distractive force can cause the newly formed mandible deviated to lingual side, and the curvature of reconstructed human mandible was less than that in the normal. It will provide a theoretical base for overcoming a less curvature of reconstructed mandible by curvilinear distraction osteogenesis in clinical application.

Key words: mandible defect, curvilinear, distraction osteogenesis, reconstruction, finite element method

中图分类号: 

• R782.2

• O242.21