Examination of factors affecting condylar bone changes following surgical-orthodontic treatment

Objective To identify factors affecting condylar bone changes following surgical-orthodontic treatment.Methods A total of 200 patients with dentofacial deformities were classified into skeletal Classes I, II, and skeletal Class III groups consisting of 61 and 139 subjects, respectively. Temporomandibular joints (TMJs) were evaluated using clinical findings and computed tomography images before treatment, immediately before surgery, and 6 months after surgery.Results Condylar bone changes occurred at a significantly higher rate after surgery in both groups. Factors related to condylar bone changes following surgical-orthodontic treatment included skeletal Class I or II, disc displacement, and condylar bone changes before treatment. There were three cases with condylar bone changes after surgery that were diagnosed with condylar resorption and skeletal Class II and anterior disc displacement before surgery.Conclusion Condylar resorption could occur when the load on the condyle increases after orthognathic surgery and exceeds the permissible limit.