Morphometric evaluation of the mandibular lingual foramen using cone-beam computed tomography: a retrospective study.

BACKGROUND

The mandibular lingual foramen (MLF) is a clinically significant structure due to its proximity to neurovascular bundles. Variations in its morphology pose risks of hemorrhage and neurosensory injury during anterior mandibular surgery. The aim of this study was to evaluate the morphometric characteristics of the MLF using cone-beam computed tomography (CBCT) and analyze its relationship with age and gender to define safe surgical boundaries.

MATERIALS AND

METHODS

A retrospective analysis was performed on 486 CBCT scans obtained from adult patients. Measurements included the number of lingual foramina, foramen diameter, canal length, distances from the alveolar crest and mandibular base, and total bone height. Gender-based comparisons were performed using Student's t-test, and correlations with age were assessed using Spearman's correlation analysis. Inter- and intra-observer reliability were evaluated using intraclass correlation coefficients (ICC).

RESULTS

A single lingual foramen was observed in 62.8% of cases, while 31.9% presented with two foramina, 4.9% with three, and 0.4% with four foramina. Male patients exhibited significantly greater vertical and horizontal bone measurements, including distances from the alveolar crest and mandibular base, total bone height, and canal length (p < 0.05). No significant gender difference was observed in foramen diameter. Age showed no correlation with foramen diameter; however, a weak but significant negative correlation was detected between age and canal length (p = 0.045). Inter- and intra-observer reliability values were excellent (ICC > 0.98).

CONCLUSIONS

The mandibular lingual foramen exhibits considerable anatomical variability influenced by gender and age. Male patients present with larger bone dimensions, while age-related bone resorption leads to a reduction in canal length without affecting foramen diameter. These findings emphasize the importance of individualized CBCT-based evaluation prior to surgical procedures in the anterior mandible to minimize the risk of complications.