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 gathered 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-radiographs, 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 anteroposterior positions of mandible and the volume of pharyngeal airway. Also, the volume of pharyngeal airway in class III patients is more than those of patients in class I. The volume of pharyngeal airway in class II patients is also less than those of class1 pa ents. Conclusion: Pharyngeal airway in class III is larger and in class II smaller. Therefore, considering this subject can lead to improving diagnostic ways, especially orthognatic surgery treatments, and providing a stable treatment plan for patients who need orthodentic treatment