فهرست نشریات علمی دسترسی آزاد ایران

Background and objectives: An essential factor in building a harmonious facial profile from an aesthetic view is the change in the gonial angle, which occurs in some orthognathic surgery cases. Occlusal plane alteration is an alternative surgical technique for optimal aesthetic results and function. This study aimed to determine the cephalometric relationship between changes in the occlusal plane and gonial angle. Materials and methods: In the present study, 76 patients who underwent bimaxillary orthognathic surgery were divided into class II and III groups. All patients had lateral cephalometric radiographs before and for a short time (maximum three weeks) after surgery. Then, cephalometric analysis of these radiographs was conducted by an orthodontist using Hexagon Imaging software, and changes in cephalometric angles were compared using two series of radiographs. Variables before and after surgery were assessed using paired t-tests, and differences in their changes were assessed using a regression test. The Pearson correlation test assessed the association of different values of the occlusal plane slope before surgery with changes in different variables. Results: Changes in the occlusal plane were not significantly associated with changes in the gonial angle. However, changes were significant regarding the relationship between the articular and gonial angles, especially in class II patients. Gonial angle also increased significantly in class II patients and slightly decreased in class III patients. In patients whose occlusal plane rotated clockwise (mean 2.6 degrees) and those whose occlusal plane rotated counter-clockwise (mean 4.06 degrees), a strong association was observed between changes in gonial angle and articular angle. Conclusion: There is no association between cephalometric changes in occlusal plane angle and changes in gonial angle in class II and III patients undergoing bimaxillary surgeries.