Objective: To determine changes in the oropharyngeal airway in Class III patients treated by bimaxillary surgery, and to find possible correlation between oropharyngeal airway changes and the skeletal movements.
Materials and Methods: Lateral cephalograms of 30 class III patients (16 females, 14 males, age: 18-25 years old) treated with maxillary advancement and mandibular set-back were evaluated pre-surgery (T1), post-surgery (T2) and 12 months post-surgery (T3). The anteroposterior oropharyngeal airway and skeletal changes of the maxilla and mandible were measured. ANOVA was performed to determine significant differences between the different time points. Pearson correlation coefficient was used to assess correlations between the changes in oropharyngeal airway and the amount of jaws movements.
Results: Parameters indicating anteroposterior maxillary position showed significant increase from T1 to T2 and from T1 to T3. Parameters indicating antero-posterior mandibular position showed significant decrease from T1 to T2 and from T1 to T3. Anteroposterior oropharyngeal airway space showed significant increase from T1 to T2 and from T1 to T3.
All measured variables in the study showed insignificant differences between T2 and T3 indicating insignificant relapse of the surgically induced changes.
Pearson's correlation analysis showed a statistically significant moderate positive correlation between the oropharyngeal airway increase and the amount of the maxillary advancement, while no correlation was found with the amount of mandibular setback.
Conclusions: Combined maxillary advancement and mandibular setback surgeries lead to an increase in the anteroposterior dimension of the oropharyngeal airway. Which is positively correlated to the amount of maxillary advancement only