Comprehensive 3D analysis of condylar morphology in adults with different skeletal patterns - a cross-sectional study

Background The correlation between individuals' condylar morphology and their skeletal pattern is of great interest for treatment strategies ranging from orthodontic orthopaedics to orthognathic surgery. The objective of the present study was to investigate this relationship three-dimensionally. Methods A total of 111 adult patients (mean age = 27.0 +/- 10.2 years) who underwent head computed tomography or cone beam computed tomography scans were included. Based on these data, 3D models of the skull and the condyles were calculated. The craniofacial skeleton was evaluated (1) transversally regarding skeletal symmetry (menton deviation), (2) sagittally regarding skeletal classes (Wits appraisal) and vertically regarding the inclination of the jaws (maxillomandibular plane angle). The condylar morphology was assessed (a) linearly by the condylar width, height and depth; (b) angularly by the antero-posterior and medio-lateral condylar inclination; and (c) volumetrically by the ratio of the condylar volume/mandibular volume (C/Mand). Results (1) Transversal: Asymmetric patients showed significantly higher discrepancies in the volumetric ratio C/Mand on the deviation and non-deviation side compared to symmetric patients. (2) Sagittal: Class III subjects demonstrated longer, more voluminous condyles with higher antero-posterior and medio-lateral inclination angles compared to Class II participants. (3) Vertical: Hyperdivergent subjects had smaller condyles with higher antero-posterior inclination angles than those of hypodivergent subjects. No interactions of skeletal class and vertical relationships regarding condylar morphology were observed. Conclusions This study demonstrates a clear correlation between pronounced skeletal patterns and condylar morphology in an adult population. The description of radiographic condyle characteristics in relation to the craniofacial morphology improves orthodontic treatment planning and could be helpful in the diagnosis of temporomandibular joint pathologies.