Two-dimensional and volumetric airway changes after bimaxillary surgery for class III malocclusion

Abstract

ObjectivesAny change in maxilla and mandible position can alter the upper airway, and any decrease in the upper airway can cause sleep disorders. Thus, it is necessary to assess airway changes after repositioning of the maxilla and mandible during orthognathic surgery. The purpose of this study was to evaluate linear and volumetric changes in the upper airway after bimaxillary surgery to correct class III malocclusion via cone-beam computed tomography (CBCT) and to identify correlations between linear and volumetric changes.Materials and MethodsThis was a prospective cohort study. CBCTs from 10 class III patients were evaluated before surgery and three months after. The Wilcoxon one-sample test was used to evaluate the differences in measurements before and after surgery. Spearman's rank correlation coefficient was used to test the correlation between linear and volumetric changes.ResultsThe results show that the nasopharyngeal space increased significantly, and that this increase correlated with degree of maxillary advancement. No significant changes were found in volumes before and after surgery. A correlation was found between linear and volumetric oropharyngeal changes.ConclusionBimaxillary surgical correction of class III malocclusion did not cause statistically significant changes in the posterior airway space.

Upper Airway 3D Changes of Patients With Cleft Lip and Palate After Orthognathic Surgery

“…As expected, a positive correlation between mCSA and NOP volume was found in both groups in the postoperative period, meaning that the larger the naso-oropharyngeal volume, the larger is the mCSA. This is in accordance with the literature (Hong et al, 2011; Jakobsone et al, 2011; Stefanovic et al, 2015; Jayaratne and Zwahlen, 2016; Vaezi et al, 2017). Additionally, UCLP group also showed a positive correlation between SNB × NOP volume and SNB × mCSA.…”

“…The results found in this study, especially for the UCLP group (Table 1), corroborates the outcomes showed in the literature for noncleft individuals, which suggests that the NP increases after maxillary advancement surgery (Jakobsone et al, 2010; Hong et al, 2011; Jakobsone et al, 2011; Stefanovic et al, 2015; Jayaratne and Zwahlen, 2016; Vaezi et al, 2017). This increase might explain the breathing and sleep improvements reported by the patients after orthognathic surgery.…”

“…It means that the more anteriorly positioned the mandible, the greater is the pharyngeal dimensions. Considering that the mCSA was located in the OP for all patients, it is expected that mandibular advancements would show proportional and direct changes in the NOP volume and mCSA, as observed in the present study (Hong et al, 2011; Jakobsone et al, 2011; Stefanovic et al, 2015; Jayaratne and Zwahlen, 2016; Vaezi et al, 2017). On the other hand, no correlation between maxillary position and the UAW dimensions was observed.…”

Orthognathic surgery for patients with idiopathic condylar resorption: Clinical research

“…According to a study by Denision et al, two-jaw surgery has low rates of open bite relapse and creates a more harmonious face [14]. However, because open bite relapse is the result of various factors, including tongue position, breathing habits, and the habit of sticking the tongue out [15], it is difficult to determine if an open bite relapse was due to skeletal instability or orthodontic causes. In addition, the most drastic changes occur in the first eight weeks following orthognathic surgery, during which period a relapse frequently occurs [16].…”

Three-dimensional analysis of changes in airway space after bimaxillary orthognathic surgery with maxillomandibular setback and their association with obstructive sleep apnea

“…Recent systemic review has concluded that there is no clear association between mandibular setback surgery and occurrence of obstructive sleep apnea (OSA) [ 6 ]. Other studies have shown that bimaxillary orthognathic surgery is less likely to induce airway obstruction or OSA compared to mandibular setback surgery as a standalone procedure [ 7 – 10 ]. However, multilevel compensative change of airway space related following bimaxillary orthognathic surgery with maxillomandibular setback is unclear.…”