Three Dimensional Study of Upper Airway in Different Antero-posterior Jaw Relationships through Cone Beam Computed Tomography

Introduction: This study aims at examining the difference of pharyngeal airways in patients with different occlusion postures, hoping to im‌prove diagnostic methods and provide a stable treatment plan for orthodontic patients. Materials and Methods: The data were ga-thered through CBCT radiographies of patients from a specialized center for radiology. In each occlusion group according to the performed pilot study, 30 people (90 people in 3 groups of class I, II and III, male and female each) were chosen as the sample. The two-di‌mentional cephalometric radiographs were ob‌tained from 3D-radio-graphs, and the patients’ malocclusion postures were de‌termined according overjet and ANB angle, and finally grouped. Next, airway volume and di‌mensions were measured in cross sectional. Results: Statistical studies showed there is a significant relationship between anteroposte-rior positions of mandible and the volume of pharyngeal airway. Also, the volume of pharyn-geal airway in class III patients is more than those of patients in class I. The volume of pha-ryngeal airway in class II patients is also less than those of class1 patients. Conclusion: Pharyngeal airway in class III is larger and in class II smaller. Therefore, consi-dering this subject can lead to improving diag-nostic ways, especially orthognatic surgery treatments, and providing a stable treatment plan for patients who need orthodentic treat-ment