LAUSR

BACKGROUND The present study evaluated the three-dimensional changes of the pharyngeal airway after orthognathic surgery (OGS) in patients with unilateral and bilateral clefts, and in unilateral cleft patients with and without pharyngeal flap (PF). METHODS Forty-five patients with unilateral or bilateral clefts receiving OGS were enrolled. Cone-beam computed tomography images were obtained before (T0) and after (T1) OGS. We measured the pharyngeal airway volumes, minimal cross-sectional area, and the horizontal displacement of facial landmarks. RESULTS The patients with bilateral cleft exhibited smaller initial velopharyngeal volume (unilateral: 8623 mm 3; bilateral: 7781 mm 3; p = 0.211), while the velopharyngeal volume increased significantly with median of 744 mm 3 after OGS (p = 0.031). The median horizontal displacement of A point was 2.9 and 2.6 mm among the patients with unilateral and bilateral clefts, respectively (p = 0.276), and the median horizontal displacement of B point was -2.9 and -3.3 mm among patients with unilateral and bilateral clefts, respectively (p = 0.618). The unilateral cleft patients with PF exhibited lower initial velopharyngeal volume (PF+: 7582 mm 3; PF-: 8756 mm 3; p = 0.129) and a lower increase in velopharyngeal volume (PF+: 437 mm 3; PF-: 627 mm 3; p = 0.739) after OGS. CONCLUSIONS Midface hypoplasia and the decrease in the velopharyngeal volume were more prominent among the bilateral cleft patients and the unilateral cleft patients with PF. After OGS, the velopharyngeal volume considerably increased among the bilateral cleft patients, but no considerable differences were noted among the unilateral cleft patients with PF.