Abstract: Objective：Study on changes of airway before and after mandibular advancement orthoganic treatment in skeletal Ⅱ adult female. Methods：Forty skeletal Ⅱ adult female patients were divided into 2 groups: orthognathic group (20 patients) and orthodontic group (20 patients). CBCT was taken before and after treatment. The airway volume and cross-sectional area were measured before and after orthodontic treatment. SPSS 25.0 was used for analyzing the changes by t test. Results：After treatment, all the measurements in the orthodontic group were not significantly changed, while the total airway volume, the minimal cross sectional area and lower cross sectional area were significantly increased in orthognathic group. Conclusions：Mandibular advancement by sagittal splint ramus osteotomy can significantly increase the airway volume, minimal cross-sectional area and lower cross sectional area in skeletal Ⅱ adult female, improve respiratory function, while orthodontic treatmenthas no significant effect on airway in these skeletal Ⅱ adult female.

Key words:

skeletal II, sagittal splint ramus osteotomy, orthodontic treatment, airway, CBCT