Computational fluid dynamics and NOSE scale to assess nasal respiratory function, and correlation with linear maxillary measurements after surgically assisted rapid maxillary expansion.

Nasal obstruction is common in patients with a transverse maxillary deficiency. The aim of this study was to determine the variation in nasal airway resistance in adult patients with a transverse maxillary deficiency before and after surgically assisted rapid maxillary expansion (SARME) by computational fluid dynamics (CFD) using computed tomography scans, and to correlate this variation with maxillary linear measurements obtained by means of plaster models. The subjective symptoms of nasal obstruction were also analysed using a visual analogue scale (VAS) for nasal breathing and the Nasal Obstruction Symptom Evaluation (NOSE) scale. There was a median reduction of 21% in nasal airway resistance post SARME (P = 0.002). The NOSE scale score decreased (P < 0.001) and nasal breathing quality VAS scores increased in both nostrils (P < 0.001). Transverse measurements between the upper canines (C-C), premolars (PM-PM), and molars (M-M), and maxillary perimeter showed significant increases (P < 0.001), while the anteroposterior maxillary arch length showed a significant decrease (P = 0.016). An inverse proportional correlation was found between PM-PM and nasal airway resistance (r = -0.395; P = 0.034) and between M-M and nasal airway resistance (r = -0.383; P = 0.040). These results demonstrate that surgically expanding the posterior region of the maxilla results in decreased nasal airway resistance, decreased obstructive symptoms, and improved patient respiratory quality.

Orthodontic measurements and nasal respiratory function after surgically assisted rapid maxillary expansion: an acoustic rhinometry and rhinomanometry study.

The present study sought to assess nasal respiratory function in adult patients with maxillary constriction who underwent surgically assisted rapid maxillary expansion (SARME) and to determine correlations between orthodontic measurements and changes in nasal area, volume, resistance, and airflow. Twenty-seven patients were assessed by acoustic rhinometry, rhinomanometry, orthodontic measurements, and use of a visual analogue scale at three time points: before surgery; after activation of a preoperatively applied palatal expander; and 4 months post-SARME. Results showed a statistically significant increase (p<0.001) in all orthodontic measurements. The overall area of the nasal cavity increased after surgery (p<0.036). The mean volume increased between assessments, but not significantly. Expiratory and inspiratory flow increased over time (p<0.001). Airway resistance decreased between assessments (p<0.004). Subjective analysis of the feeling of breathing exclusively through the nose increased significantly from one point in time to the next (p<0.05). There was a statistical correlation between increased arch perimeter and decreased airway resistance. Respiratory flow was the only variable to behave differently between sides. The authors conclude that the SARME procedure produces major changes in the oral and nasal cavity; when combined, these changes improve patients' quality of breathing.