CBCT Evaluation of the Mandibular Foramen According to Age, Sex, and Sagittal Skeletal Class in Growing Individuals

Abstract

Highlights What are the main findings? • Statistically significant age-group differences were detected only for the M2 measurement, whereas no statistically significant differences according to sex or sagittal skeletal class were detected in this sample. Elliptical morphology was the most frequently observed form bilaterally. What are the implications of the main findings? • The findings provide CBCT-based anatomical information on mandibular foramen measurements and morphology in growing individuals. The clinical implications of the observed M2 differences require cautious interpretation because anesthetic and surgical outcomes were not evaluated. Abstract Objective: This study aimed to describe the CBCT-based positional measurements and morphological distribution of the mandibular foramen in growing individuals and to compare the M1, M2, and M3 measurements according to chronological age group, sex, and sagittal skeletal class. Materials and Methods: This retrospective cross-sectional study included 120 CBCT images of individuals aged 6–16 years (mean 10.31 ± 2.33 years; 67 male, 53 female) selected from 750 archived scans. Participants were divided into three age groups (6–8, 9–12, and 13–16 years) and classified using the ANB angle (Class I, II, and III). Three measurements were assessed: M1 (foramen to occlusal plane), M2 (to posterior ramus border), and M3 (to anterior ramus border). Foramen morphology was classified into five types: circular-, elliptical-, triangular-, rectangular-, and parallelogram-shaped. The Mann–Whitney U and Kruskal–Wallis tests were used, followed by Bonferroni-adjusted pairwise comparisons where appropriate. Results: Interobserver ICC values ranged from 0.75 to 0.81, indicating good interobserver reliability. In the unadjusted comparisons, no statistically significant differences in M1, M2, or M3 were detected according to sex or sagittal skeletal class (all p > 0.05). Significant age-related differences were identified in M2 between the 6–8 and 9–12 year groups (right p = 0.003; left p = 0.021) and between the 6–8 and 13–16 year groups (right p < 0.001; left p = 0.003). Elliptical morphology was most prevalent bilaterally (right 39.2%; left 40.0%). Conclusions: Statistically significant age-group differences were detected only for M2, whereas no statistically significant differences according to sex or sagittal skeletal class were detected in this sample. Greater M2 values in the older age groups represent a greater absolute linear distance between the fixed mandibular foramen reference point and the posterior ramal reference line and should not be interpreted as evidence of posterior displacement. Elliptical morphology was the most frequently observed form bilaterally. These findings provide anatomical information from clinically indicated CBCT examinations but do not support routine CBCT acquisition solely for mandibular foramen localization.