ABSTRACT
Objective:To analyze the differents in the upper airway morphology and hyoid position between skeletal class III malocclusion of high-angle and normal occlusion by cone beam CT(CBCT), and to study the influence of skeletal class III malocclusion of high-angle in the upper airway and hyoid position of the adults preliminarily.Methods:A total of 42 adults in Department of Orthodontics, Dalian Stomatology Hospital were chosen, including 21 adults with skeletal class III malocclusion of high-angle and 21 adults with normal occlusion. MIMICS 20.0 software was used to measure the line spacing, cross-sectional area and volume of each upper airway segment and line distance of hyoid of the patients on CBCT; SPSS 20.0 software was used for statistical analysis.Results:Compared with normal occlusion group, the maximum lateral distance (LAT1) of the nasopharynx, the maximum anterior-posterior distance (AP2) of the velopharyngeal, and the volume of the velopharyngeal (VOL2) of the patients in skeletal class III malocclusion of high-angle group were increased (P0.05)Conclusion:Cross-sectional area and volume of velopharyngeal have the tendency of increase, but cross-sectional area and volume of laryngopharynx have the tendency of decrease in the patients with skeletal class ? malocclusion of high-angle. The hyoid bone has a tendency to shift forward and upward in the patients with skeletal class ? malocclusion of high-angle.