Postoperative Skeletal Stability and Pharyngeal Airway: Counterclockwise versus Clockwise Rotation during Mandibular Setback Surgery

Figure 1

Landmarks, reference lines, distances, angles, and pharyngeal airway measurements. X, horizontal line; Y, vertical line; S, sella; N, nasion; Me, menton; H, hyoid bone; ANS, anterior nasal spine; PNS, posterior nasal spine; U, tip of uvula; TP, tongue posterior; C2, inferoanterior point on the second cervical vertebra; C4, inferoanterior point on the fourth cervical vertebra; E, most superior point on the epiglottis. Green lines: C2C4 line; ANS-PNS line. Brown arrow: (1) soft palate angle (ANS-PNS-U angle) and (2) cervical vertebral angle (C4C2-SN angle). Red lines: (3) SPL (length of the soft palate); (4) SPW (widest distance of the soft palate); (5) NOP (nasal pharyngeal airway); (6) UOP (uvula pharyngeal airway); (7) TOP (tongue pharyngeal airway); (8) EOP (epiglottis pharyngeal airway). Purple: (9) (counterclockwise rotation) Blue: 10 (clockwise rotation).