Comparison of surgical and non-surgical orthodontic treatment approaches on occlusal and cephalometric outcomes in patients with severe Class II division I malocclusions

This study aimed to examine end-of-treatment outcomes of severe Class II Division I malocclusion patients treated with surgical or non-surgical approaches. This study tests the hypotheses that occlusal outcomes (ABO-OGS) at end of treatment will be similar while cephalometric outcomes will differ between these groups. A total of 60 patients were included: 20 of which underwent surgical correction and 40 of which did not. The end of treatment ABO-OGS and cephalometric outcomes were compared by Mann-Whitney U tests and multivariable linear regression models. Following adjustment for multiple confounders (age, gender, complexity of case, and skeletal patterns), the final deband score (ABO-OGS) was similar for both groups (23.8 for surgical group versus 22.5 for non-surgical group). Those treated surgically had a significantly larger reduction in ANB angle, 3.4 degrees reduction versus 1.5 degrees reduction in the non-surgical group (p=0.002). The surgical group also showed increased maxillary incisor proclination (p=0.001) compared to candidates treated non-surgically. This might be attributed to retroclination of incisors during treatment selection in the non-surgical group – namely, extraction of premolars to mask the discrepancy. Studies such as this are necessary because they begin to give practitioners view of not only the outcomes of a single treatment plan, but a comprehensive approach by providing evidence of the over-arching treatment used for successful treatment in both groups.