Dentoalveolar Markers in A Group of Turkish Population with Different Anteroposterior Relationships: A CBCT Retrospective Study

Objective: To assess collum angle and alveolar bone thickness across different anteroposterior incisor relationships using cone-beam computed tomography (CBCT), and to analyze the correlations between these morphological parameters. Materials and Methods: This retrospective CBCT study included 200 Turkish patients (12–37 years) categorized according to the British Standards Institution (BSI) incisor classification: Class I, Class II/1, Class II/2, and Class III. Collum angle and buccal, palatal, and lingual alveolar bone thicknesses were measured on maxillary and mandibular anterior teeth and premolars at 5 mm apical to the CEJ using standardized sagittal slices. Results: Collum angle varied significantly among malocclusion groups, with the greatest values observed in Class II/2 and Class III individuals. Mandibular teeth consistently exhibited positive collum angles, whereas maxillary teeth showed class-dependent variation. Buccal bone thickness was substantially reduced in Class III mandibular incisors and canines, while Class II/2 subjects presented increased palatal thickness in selected maxillary teeth. Correlation analysis revealed tooth- and class-specific associations, including a moderate negative correlation between collum angle and buccal thickness in Class II/2 maxillary central incisors, and a strong positive correlation with lingual thickness in Class III mandibular lateral incisors. Conclusion: Collum angle and alveolar bone thickness exhibit distinct, class-dependent morphological patterns that may restrict the biomechanical limits of orthodontic tooth movement. The pronounced root inclinations and reduced alveolar support in Class II/2 and Class III patients underscore the need for detailed CBCT evaluation to prevent periodontal complications during treatment.