Diagnostic criteria in the planning of orthodontic-surgical treatment of skeletal malocclusions

Abstract

Background: Orthodontic-surgical planning is based on precise cephalometric investigations, which highlight dentoalveolar compensations that require preoperative decompensation. Soft tissue profile analysis (according to Arnett) complements the esthetic evaluation, while CBCT provides information regarding alveolar bone sufficiency for planning dental movements. Objective of the study: to describe the diagnostic criteria and the clinical reasoning that led to the selection of an integrated orthodontic-surgical strategy in a clinical case with skeletal Class III malocclusion according to Angle, associated with maxillary constriction and transverse deficiency. Material and methods: A 27-year-old female patient presented with skeletal Class III malocclusion according to Angle, with severe maxillary constriction. Preoperative orthodontic treatment with a fixed appliance was initiated, followed by dental alignment and decompensation, achieving adequate sagittal relationships and functional anterior contact. However, CBCT analysis confirmed a transverse osseous deficiency, which contraindicated purely orthodontic expansion. Thus, a complex orthodontic-surgical treatment was planned, consisting of bimaxillary osteotomy with maxillary segmentation for correction of the transverse discrepancy. Results: The respective case highlights the importance of integrated orthodontic-surgical planning, based on cephalometric analysis and three-dimensional CBCT evaluation. Establishing the biological limits of dental movements is essential to avoid unstable compensations. Although decompensation allowed sagittal correction, transverse analysis demonstrated the necessity of a complex approach. Rigorous planning facilitated the selection of multisegmental osteotomy to obtain functional and stable occlusion. Conclusions: Orthognathic treatment of skeletal discrepancies requires integration of three-dimensional diagnosis and proper orthodontic biomechanics. Dental decompensation ensures correct sagittal relationships but cannot substitute surgical correction in cases with severe transverse deficiency. Segmental maxillary osteotomy allows augmentation of osseous defects, restoration of the transverse dimension, and achievement of long-term stable functional occlusion.