Evaluation of soft tissue changes around the nose following subspinal Le Fort Ⅰ osteotomy

This study sought to evaluate the effect of subspinal Le Fort Ⅰ osteotomy (SLFⅠO) and alar base chinch suture (ABCS) in preventing postoperative changes of nasal shape following maxillary movement of advancement-impaction (MAI) or advancement-downward (MAD) by analyzing changes of nasal soft tissue on computed tomography (CT) images. Forty-three Japanese patients with dentofacial deformity who underwent orthognathic surgery with SLFⅠO and ABCS were retrospectively examined. Maxillary movement and changes to soft tissues around the nose were analyzed using pre- and postoperative CT. Increased nasal width and alar base width, upturning of the nasal tip and flattening of the nose occurred in both groups, with more prominent changes in MAI. MAD showed horizontal maxillary movement strongly correlated with changes in pronasale and subnasale. Preoperative nasal height correlated negatively with changes to nasal height in both groups, and to nasolabial angle and nasal tip angle in MAD. There were no correlations between the tightness of ABCS during operation and postoperative nasal soft tissue changes including nasal width. Postoperative changes to nasal shape following SLFⅠO and ABCS need to be considered with advance movements of the maxilla, regardless of vertical maxillary movement. Postoperative pronasale and subnasale may be estimable from the amount of the maxillary advance movement in MAD. Postoperative changes in nasal shape may be more prominent in cases with low nasal height.