骨性III类错牙合畸形患者正颌术后口咽气道变化的研究

Changes of oropharyngeal airway after orthognathic surgery in patients with skeletal class III malocclusion

摘要:

目的 分析和测量下颌骨后退量对骨性Ⅲ类错牙合畸形患者正颌术前、术后口咽气道容积的变化。方法 选取19例下颌前突和ANB角小于-2°诊断为骨性Ⅲ类错牙合畸形的患者，其中男6例，女13例，按照正颌手术中下颌骨后退量分为两组，实验Ⅰ组：下颌后退量<5 mm，共9例；实验Ⅱ组：下颌后退量 ≥ 5 mm，共10例。所有患者采用双侧下颌骨升支矢状劈开截骨后退（BSSRO）术进行治疗，患者均在正颌外科手术前1周和术后3~6个月分别行CT和肺功能检查。应用 Mimics 21.0软件进行图像处理和测量研究，使用SPSS 23.0软件对所有测量值进行统计学分析。观察患者下颌骨后退量与口咽气道的关系。结果 在腭咽段，两组治疗后与治疗前相比，腭咽段术后各组数据均较术前有所增大，但经配对t检验，差异无统计学意义（P>0.05）。在舌咽段，两组手术后数值均减小，在横截面积和容积方面，两组的减小量有显著差异（P<0.05），即实验Ⅱ组较实验Ⅰ组减小更加明显。结论 正颌手术中BSSRO术会引起骨性III类错牙合畸形患者舌咽段横截面积和容积明显减小，下颌骨后退量较大者舌咽段气道横截面积和容积减小明显。

Abstract:

Objective To measure and analyze the effect of the amount of mandible setback on the oropharyngeal airway in patients with skeletal class III malocclusion. Methods Nineteen patients (13 females and 6 males) with skeletal class Ⅲ malocclusion were divided into two groups according to the amount of mandible setback. GroupⅠ(9 patients) had the amount of mandible setback less than 5mm and groupⅡ(10 patients) equal to or more than 5mm. All patients underwent bilateral sagittal split ramus osteotomy (BSSRO) for mandible setback. They received CT scanning and pulmonary function examination 1 week before and 3 to 6 months after surgery. Mimics 21.0 software was used for image processing and measurement, and SPSS 23.0 software was used for statistical analysis. Results In velopharynx, the values of both groupⅠand II were increased after surgery, but the differences were statistically insignificant (both P>0.05). In glossopharynx, the values of groupⅠand II were both decreased after surgery. The reductions of the cross-sectional areas and volumes in group II were more obvious than groupⅠ, and the differences were statistically significant (both P<0.05). Conclusion In orthognathic surgery, BSSRO causes significant reduction in the cross-sectional areas and volumes of the glossopharyngeal segment in patients with skeletal class III malocclusion, and the patients with greater amount of mandible setback may have more reduction.