Sex differences in pharyngeal airway morphology in adults with skeletal Class III malocclusion.

OBJECTIVES: To compare the pharyngeal airway dimensions in adults with skeletal Class III malocclusion and well-balanced faces, to ascertain whether sex can influence such measurements and to correlate skeletal pattern with pharyngeal dimensions.

METHODOLOGY: Fifty adults were recruited and assigned to two groups: skeletal Class III (n = 25; 12 males and 13 females, mean age = 26.1 years), and skeletal Class I (n = 25; 11 males and 14 females, mean age = 26.0 years), with well-balanced faces. Pharyngeal measurements were made using cone beam computed tomography and analyzed with Dolphin Imaging software 11.5.

RESULTS: Pharyngeal sagittal area, length, retroglossal area and width were statistically greater for males. Pharyngeal volume was greater for Class III patients (p = .0245), due to enlarged male dimensions. A significant but moderate correlation was observed between pharyngeal airway volume and ANB angle (r = -.4917) and effective mandibular length (Co-Gn, r = .5181).

CONCLUSION: There is sexual differentiation in the pharyngeal airway morphology for Class III adults. As females present similar pharynx volume compared to a normal skeletal pattern, mandibular setback surgery should be carefully planned because of the risk of airway constriction.