Correlation between upper airway morphological changes and jaw movement after bimaxillary orthognathic surgery in pa-tients with skeletal Class Ⅲ malocclusion
Objective To investigate the morphological changes in the upper airway after bimaxillary surgery in patients with skeletal Class Ⅲ malocclusion and the relationship between jaw movement and airway changes using CBCT.Methods This study involved 44 individuals(21 males and 23 females)receiving Class Ⅲ bimaxillary surgery.Preoperative and 3-6-month postoperative CBCT data were examined using Dophin3D 11.95 software.The alterations before and after upper airway surgery were analysed using paired t-test and non-parametric Wilcoxon rank sum test.The association between airway alterations and jaw movement was examined using Pearson's correlation coefficient.Results Patients who underwent Class Ⅲ bimaxillary surgery had significantly reduced upper airway volume,sagittal cross-sectional area,and minimum cross-sectional area(P<0.01).A correlation exists between oropharyngeal volume change and point B change(P<0.05).When B point recession was>7 mm,the decrease in upper airway volume increased significantly(P<0.01),as did the risk of minimum cross-sectional area of the patient's airway(P<0.01).Conclusion ClassⅢbimaxillary surgery re-duces upper airway capacity.Postoperative reduction in upper airway capacity coincides with mandibular recession.Mandibular reces-sion(>7 mm)may reduce postoperative upper airway capacity and increase the risk of OSAHS.Patients at risk of upper airway stenosis should have their protocol modified to reduce airway risk.
skeletal Class Ⅲ malocclusionbimaxillary orthognathic surgerypharyngeal airwaycone-beam computed tomography