Assessment of the Impact of Two-Jaw Orthognathic Surgery on Three-Dimensional Airway Volume in Patients with Skeletal Class III Patterns

Objective To evaluate 3-dimensional pharyngeal airway changes following 2-jaw orthognathic surgery in skeletal Class III patients and to assess their association with surgical movements. Design Retrospective observational study. Setting Single tertiary care center. Patients Twenty-seven adult patients with skeletal Class III malocclusion who underwent Le Fort I maxillary advancement combined with bilateral sagittal split osteotomy mandibular setback. Interventions All patients received 2-jaw orthognathic surgery with preoperative (T0) and postoperative (T1, 6 months) computed tomography imaging. Main Outcome Measures Three-dimensional airway volumes of the nasopharynx, oropharynx, and hypopharynx were measured. Correlations between airway volume changes and skeletal movements were analyzed. Results Significant regional differences in airway changes were observed. The nasopharyngeal airway volume increased (+1979.1 mm 3 ), while the oropharyngeal airway showed minimal change (+336.4 mm 3 ). In contrast, the hypopharyngeal airway demonstrated a significant reduction (−1087.5 mm 3 ). A strong correlation was found between mandibular setback and hypopharyngeal airway reduction at Point B (r = 0.73, P = .023). Conclusions Two-jaw orthognathic surgery results in region-specific airway changes. Hypopharyngeal airway reduction is associated with mandibular setback, while maxillary advancement contributes to upper airway enlargement. These findings reflect morphological rather than functional changes, and further studies incorporating functional assessments are required to determine their clinical significance.