Cone beam computed tomography (CBCT) records of 62 non-growing patients were used to evaluate the pharyngeal airway volume (upper and lower components), and the shape of the airway, using semi-automatic segmentations to calculate real volumes instead of estimates based on linear measurements. The sample was divided according to anteroposterior jaw relationships and vertical proportions. There was a statistically significant relationship between the volume of the lower component and a-p jaw relationship, and between airway volume and both the size of the face and gender. No differences in airway volumes related to vertical facial proportions were observed. Skeletal Class II patients tended to display forward inclination of the airway, greater projection of the tongue into the airway, and narrower airways. Skeletal Class III patients usually had a vertically-oriented airway. This study is a pioneer in measuring real 3-D models and controlling for face size.