Three-Dimensional Evaluation of the Upper Airway after Orthognatic Surgery in Angle Class II and Class III Patients

Abstract

Aims: Orthognathic surgeries aim to correct dentoskeletal discrepancies and thus reestablish the patient's facial harmony and ideal occlusion. The objective of this observational cohort study was to evaluate in three dimensions (3D) the volume and minimum axial area of ​​the upper airway (UA) after 180 days of orthognathic surgical procedures performed in the maxilla, mandible and chin in patients with type II and III malocclusion. Study Design:  Observational study. Place and Duration of Study: The sample came from patients who underwent bimaxillary orthognathic surgery for Angle Class II and Class III correction between 2018 and 2019 in a private clinic, consisting of 58 patients. Methodology: Through the analysis of computed tomography (CT) scans of patients admitted to bimaxillary surgery with virtual planning, the preoperative (T1) and 180-day post operative (T2) moments were evaluated using the Dolphin Imaging® software. The sample came from the analysis of the clinical records of patients admitted to surgery between the years 2017 and 2019. Results: Among the 50 records analyzed, 16 were excluded from the research because they did not meet the eligibility criteria, or due to problems arising in reading the software. Of those eligible, measurements were taken of: total volume and minimum axial area of ​​the upper airway. Patients undergoing orthognathic surgery for class II showed a significant difference after performing medical therapy with an increase in minimum values ​​in total area and axial area, unlike class III patients, who did not present a significant difference (p≤0.05). Conlusions: Class II patients had a significant increase in UAV, while class III patients did not present a significant change in UAV. The importance of good planning and combined movements make orthognathic surgery increasingly predictable and with better results.