Comparative Evaluation of Buccal Cortical Bone Thickness in the Posterior Mandible Across Skeletal Patterns: A CBCT Study in a Sample of Iranians.

PURPOSE: This study aimed to evaluate buccal cortical bone thickness in the posterior mandible across different sagittal and vertical skeletal patterns using cone-beam computed tomography (CBCT).

MATERIALS AND

METHODS

In this retrospective observational study, cortical buccal bone thickness between posterior teeth was assessed at 4 and 7 mm distances from the alveolar crest using CBCT images of 112 Iranian participants aged 18-60 years. Participants were classified into six groups: Class I normal angle, Class I low angle, Class I high angle, Class II normal angle, Class II low angle, and Class II high angle. Statistical analyses included the Shapiro-Wilk test, Levene's test, multivariate analysis of variance (MANOVA), paired-sample t-test, and intraclass correlation coefficient (ICC), with a significance level set at α = 0.05.

RESULTS

Cortical bone thickness generally increased from anterior to posterior regions and from the alveolar crest toward the basal jaw in Class II and both high- and low-angle groups, with exceptions observed in Class I and normal-angle individuals. Statistically significant differences in cortical bone thickness were observed between Class I and Class II skeletal patterns at specific posterior sites, with Class I individuals consistently exhibiting greater thickness. Differences related to vertical skeletal pattern were limited, observed only at the distal canine (4-mm level). Sex, age, and side-to-side differences influenced cortical thickness in certain regions, with slightly greater thickness on the left side at some measurement sites.

CONCLUSIONS

Buccal cortical bone thickness in the posterior mandible varies significantly with the sagittal skeletal pattern, whereas the vertical skeletal pattern has minimal influence.