Avaliação da posição do osso hióide e volume da via aérea em pacientes submetidos a cirurgia ortognática bimaxilar

Abstract

The aim of this study was to evaluate changes in hyoid bone and pharyngeal airway space (PAS) position in patients with class II and III skeletal deformities who underwent bimaxillary orthognathic surgery. Furthermore, we sought to correlate the spatial position of the hyoid bone with the upper airways. Eighty patient datasets were selected, divided into two groups (Class II and Class III). Analyzes were performed in cone beam tomography scans, at times T0 (preoperative) and T1 (6 months postoperative), to quantify three-dimensional changes in the spatial position of the hyoid bone and changes in area and volume in the total PAS, oropharynx and hypopharynx. Statistics were performed using paired t tests and Wilcoxon test, in addition to Spearman's correlation. The level of significance considered was 5%. In class II patients, significant changes were found in the position of the hyoid bone of 2.65 mm of advancement and 2.45 mm of superior displacement, in addition to significant gains in all PAS regions studied in this group. In class III patients, no significant changes in hyoid position or PAS were observed. Positive and negative correlations were seen between hyoid and PAS in both groups. Bimaxillary advancement orthognathic surgery provides significant gains in PAS in class II patients and class III without statistical significance. Surgeries with mandibular setback in class III patients did not show significant negative repercussions. Within the limitations of this study, the anteroposterior position of the hyoid bone does not seem to influence the pharyngeal air space after bimaxillary orthognathic surgery.