Condylar morphology in skeletal Class II malocclusion: relationship to mandibular retrognathia and airway stenosis

This study aimed to establish a novel cone-beam computed tomography (CBCT)-based classification of temporomandibular joint (TMJ) condylar morphology and investigate its correlation with mandibular retrognathia and airway stenosis in skeletal Class II malocclusion. In total, 353 patients were retrospectively analyzed. The condylar morphology was classified into three types (normal, erosion, and stump; NES classification) based on coronal axis CBCT shape. Condylar height, width, and radian value (R) were measured. Mandibular retrognathia was assessed cephalometrically, and airway dimensions were evaluated. Statistical analyses included ANOVA, chi-squared test, and correlation analysis. Among the patients, 302 (85.6%) exhibited bilateral symmetrical morphology, and correlation analysis was performed on these 604 condyles. A significant association existed between morphological subtypes and mandibular retrognathia severity. The stump type, indicating severe degeneration, correlated with the greatest skeletal discrepancy (ANB angle: 10.7° ± 1.2) and the narrowest oropharyngeal airway diameter (4.3 ± 1.8 mm). A strong correlation was found between the R value and key indicators of mandibular retrognathia and airway stenosis. The CBCT-based NES classification effectively links condylar morphology to the severity of mandibular retrognathia and airway stenosis. It serves as a clinically useful tool for improving risk stratification and facilitating personalized treatment planning in skeletal Class II patients.