Radiographic Analysis of Posterior Airway Variation, Gonial Angle, Mandibular Length and Facial Height in Patients Submitted to Vertical Mandible Osteotomy

Introduction: Facial deformities have always attracted the attention of surgeons, and the most prominent is the so-called mandibular prognathism. It is a fact that the stability of any osteotomy of the mandibular branch is affected by the amount of retrusion, the fixation method, and the growth. Objective: The objective of the present study was to evaluate radiographically the variations of pharyngeal airspace, facial height, mandibular length and gonial angle in patients with Class III dento-skeletal deformity submitted to vertical osteotomy of the mandibular branch for indentation. Methods: Analysis of Teleradiographs done before and after Jaw Vertical Osteotomy of 39 patients (20 females and 19 males). In the present retrospective study, we evaluated quantitatively lateral cephalometric radiographs of patients of both genders, who needed to undergo vertical osteotomy of the mandibular branch to correct dento-skeletal deformity of the Class III type, whose purpose was to mandibular retreat. Results: There were mandibular retreatments with a decrease in mandibular length (100%) with a change in the amount of indentation in millimeters with an amplitude of 2 mm to 22 mm and linear (23.1%) or rotational movement (time: 30.8%; counterclockwise: 44%). The cases submitted to Mandibular Intraoral Vertical Osteotomy showed a reduction of the Gonial Angle in 13 cases. The parametric linear regression test revealed for all variables that there was no significant statistical difference between the SN_pre and SN_post variables; AF_pre and AF_post; CM_pre and CM_post; EA_pre and EA_post, and between AG_pre and AG_post, with p<0.05. Conclusion: After evaluating radiographically the pharyngeal airspace, facial height, mandibular length, and gonial angle, it was analyzed that there were mandibular retreatments with decreased mandibular length with a change in the amount of indentation and linear or rotational movement.