RESUMO
OBJECTIVE: The aim of this study was to evaluate alterations in condylar positioning through submentovertex projection (Hirtz Radiographic Technique) in patients who underwent orthognathic surgery for maxillary advancement and mandibular setback with stable internal fixation. METHODS: A prospective longitudinal clinical study of 40 surgical patients presenting dentofacial deformity admitted in the Oral and Maxillofacial Surgery Department of Federal University of Paraná (UFPR) in the period between March 2013 and December 2015. We performed two submentovertex digital radiographs, one 7 days before surgery and the other one 30 days after the procedure. Cephalometric tracings were made using Radiocef® Studio 2 Software and measured the intercondylar and condylar angles (right and left). RESULTS: There was a decrease in the intercondylar angle (p < 0.001) and an increase in condylar angles both the right and the left side (p < 0.001) when compared with the pre and postoperative period. There was a larger increase in condylar angle on the right side in males (p = 0.007). CONCLUSION: There is a tendency of decreasing of the intercondylar angle after orthognathic surgery, regardless of the alteration in the condylar angles, creating a new position of the condyle in the glenoid fossa. Patients with asymmetry may present greater alterations in the positioning of the opposite condylar to the deviation of the mandibular midline.