Evaluation of mandibular anterior alveolar bone thickness in various skeletal malocclusions and its relationship with symphysis morphology in Tamil Nadu population: a CBCT study

Background and Objective The natural physiological structure of the alveolar bone significantly influences the movement of the anterior teeth during orthodontic treatment. This study aimed to assess the alveolar bone thickness (ABT) of mandibular anterior teeth at three levels using Cone Beam Computed Tomography (CBCT) in individuals with different anteroposterior skeletal malocclusions and to explore its relationship with symphysis dimensions.Materials and Methods Sixty CBCT scans were analysed from untreated adult subjects in their naturally compensated state to minimize treatment-related variation. The subjects were divided into three skeletal malocclusion groups (Class I, II, and III). Three labial measurements were recorded at 3 mm and 6 mm from the cementoenamel junction (CEJ), and at the root apex level. Similarly, three lingual measurements were taken at 3 mm and 6 mm from the CEJ, and at the root apex level. . Symphysis dimensions, including height and buccal/lingual width, were also assessed. Statistical analysis included ANOVA, Bonferroni post hoc test and Pearson correlation.Results Class I patients showed significantly greater ABT than Class II and III at specific sites, particularly at 6 mm from the CEJ and apex labially in the mandibular central incisors and 3 mm,6 mm from the CEJ lingually and apex lingually in the mandibular canine. A positive correlation between symphysis dimensions and ABT was found in Class III malocclusions, while Class II malocclusions exhibited a negative correlation.Conclusion Mandibular anterior alveolar bone thickness and symphysis morphology varied significantly across skeletal malocclusions. Class III subjects exhibited reduced labial alveolar support, while Class II subjects showed greater symphysis dimensions. These variations underscore the importance of individualized diagnosis and meticulous planning of incisor movements to minimize iatrogenic effects.