Quantitative Evaluation of the Postoperative Changes in Nasal Septal Deviation by Diverse Movement of the Maxilla After Le Fort I Osteotomy.

The purposes of this study were to compare the postoperative changes in nasal septal (NS) deviation between total impaction (TI) and anterior elongation (AE) of the maxilla after Le Fort I osteotomy (LF-IO) and to investigate the correlation between the change in NS deviation and the amount of surgical maxillary movement. Twenty-eight patients, who underwent LF-IO and sagittal split osteotomy by a single surgeon, were divided into TI group (N = 13; mean = 1.5 mm) and AE group (N = 15; mean = 1.6 mm). NS deviation was measured using computed tomography and deviation indices before and after surgery at 3 coronal measurement planes (CMP) passing through the nasion, crista galli, and the most anterior point of the sphenoid sinus (MAPS). Then, statistical analysis was performed. The AE group did not have significant changes in any deviation indices after surgery. The TI group; however, exhibited significant increases in the MAPS-CMP and total deviation indices (0.67-1.16 mm, P < 0.01; 5.45-6.43 mm, P < 0.05). The TI group also exhibited a greater increase in the ΔMAPS-CMP deviation index than the AE group (0.49 mm versus 0.06 mm, P < 0.05). The amount of forward movement of the maxilla was positively correlated with the nasion-CMP and total deviation indices (r = 0.422, P < 0.05; r = 0.398, P < 0.05). LF-IO for TI and forward movement can worsen NS deviation posteriorly and anteriorly, respectively. It is necessary to manage the nasal septum and the nasal crest of the maxilla meticulously during LF-IO procedure.