METHODS: Nine models were constructed to scrutinize the effects of pterygomaxillary disjunction (PMD), lateral osteotomy positioning, and TPD placement on displacement profiles and Von Mises stresses. These models encompassed variations such as no, unilateral or bilateral PMD, asymmetrical lateral osteotomy, and five TPD locations.
RESULTS: Performing a PMD reduces posterior resistance to transverse expansion, resulting in 10-20 % stress reduction around the maxillofacial complex. No significant changes in horizontal tipping were observed post-PMD. The asymmetric lateral osteotomy model exhibited larger displacements on the side with a more superiorly positioned osteotomy. Reduced stresses were observed at the maxillary body and medial pterygoid plate (superiorly), while increased stresses were observed at the medial (inferiorly) and lateral pterygoid plates. More posterior TPD placement facilitated more parallel expansion thus less horizontal tipping, albeit with increased vertical tipping.
CONCLUSIONS: SARPE procedures (distractor and osteotomy positions) can be tailored based on desired outcomes. PMD reduces stress within the maxillofacial complex but doesn\'t significantly affect tipping. Higher lateral osteotomies lead to increased displacements, more posterior distractors to more parallel expansion.
方法:构建了九个模型来仔细检查翼状腋窝脱落(PMD)的影响,外侧截骨定位,和TPD放置在位移剖面和VonMises应力上。这些模型包含了诸如无,单侧或双侧PMD,不对称外侧截骨,和五个TPD地点。
结果:进行PMD可降低横向扩张的后部阻力,导致颌面复合体周围10-20%的应力降低。PMD后未观察到水平倾翻的显着变化。不对称的外侧截骨模型在一侧显示出较大的位移,而截骨的位置更高。在上颌体和内侧翼状骨板(上方)观察到应力降低,而在内侧(下方)和外侧翼状板观察到应力增加。更多的后部TPD放置促进了更多的平行扩张,从而减少了水平倾斜,尽管垂直倾斜增加。
结论:SARPE手术(牵引器和截骨位置)可根据预期结果进行调整。PMD可降低颌面部复合体内的应力,但不会显着影响倾翻。较高的外侧截骨术导致位移增加,更多的后部撑开器到更多的平行扩张。