2种不同正颌术式对骨性Ⅲ类错畸形患者上气道形态的影响

目的： 建立骨性Ⅲ类错畸形患者正颌手术前、后上气道三维模型，比较不同正颌术式对骨性Ⅲ类错畸形患者上气道各截面积及容积的影响。方法： 28例骨性Ⅲ类错畸形患者经正颌-正畸联合会诊，制定手术方案，分为2组，实验A组（12例）为单纯双侧下颌支矢状劈开术（BSSRO）后退，即单颌手术组，实验B组（16例）为下颌骨BSSRO 后退 +上颌骨Le Fort I型截骨术前移，即双颌手术组。所有患者于正颌手术前（T1）和术后3个月（T2）分别行CT扫描，基于CT图像，应用Dolphin Imaging 11.7软件建立包含腭咽、舌咽和喉咽腔在内的上气道三维模型，测量、比较2组患者在正颌手术前、后的上气道各截面、腔隙的矢状径、冠状径、横截面积和容积改变的差异。采用SPSS 16.0 软件包进行统计学分析。结果： 在腭咽段，实验A组手术后各项数值均较术前减小；实验B组手术后除冠状径外，其余数值均较术前增大，且2组变化有显著差异（P<0.05）。在舌咽段及喉咽段，2组手术后数值均减小。在横截面积和容积方面，实验A组较实验B组减小更加明显，2组的减小量有显著差异（P<0.05）。结论： 与单颌手术相比，双颌手术对骨性Ⅲ类错畸形患者上气道形态的减小改变影响较小。

Evaluation of the effects of two different modes of orthognathic surgery on upper airway morphology in patients with skeletal Class Ⅲ malocclusion

PURPOSE: To establish three-dimensional models of upper airway pre- and post-orthognathic surgery in patients with skeletal Class Ⅲ malocclusion, and to compare the effects of different modes of orthognathic surgery on the cross-sectional areas and volumes of upper airway. METHODS: Twenty-eight patients with skeletal Class Ⅲ malocclusion were divided into 2 groups. Group A (12 patients) underwent bilateral sagittal split ramus osteotomy(BSSRO) for mandibular setback, named single jaw surgery group; group B (16 patients) underwent BSSRO + Le Fort I osteotomy for mandibular setback and maxillary advancement, named bimaxillary surgery group. All patients received CT scanning before (T1) and 3 months after surgery (T2). The three-dimensional models of the upper airway containing velopharynx, glossopharynx and laryngopharynx were established by using Dolphin Imaging 11.7 software. The changes of sagittal diameters, coronal diameters, cross-sectional areas and volumes of the upper airway were measured and compared between the two groups pre- and post- surgery (T1, T2) using SPSS 16.0 software package, respectively. RESULTS: In velopharynx, the values of group A were decreased after surgery, while the other values of group B were increased except the value of coronal diameter. There was a significant difference between the two groups (P<0.05). In glossopharynx and laryngopharynx, the values of group A and group B were both decreased after surgery. The reduction of the cross-sectional areas and volumes in group A were more obvious than group B (P<0.05). CONCLUSIONS: The amount of narrowing of the upper airway is smaller in patients undergoing bimaxillary surgery than in patients undergoing mandibular setback surgery.