Morphometric analysis of the mandibular incisive canal using cone beam computed tomography images

The mandibular incisive canal (MIC), an anterior extension of the inferior alveolar canal, contains neurovascular bundles and is clinically significant. On cone beam computed tomography (CBCT) scans, it appears as a radiolucency with a radiopaque rim. This study aimed to investigate anatomical variations of the mandibular incisive canal using CBCT images from patients referred to treatment centers in Tehran during 2023–2024. In this cross-sectional study, 345 CBCT scans (690 images) from patients referred to medical centers in Tehran were analyzed. The MIC’s length, diameter, and distances from anatomical landmarks were measured. Data were analyzed using descriptive statistics, chi-square tests, t-tests, ANOVA, and Mann-Whitney tests. The mandibular incisive canal was identified in 74.5% of patients and 60.6% of CBCT images. The mean length and diameter of the MIC were 13.7 ± 3.90 mm and 1.65 ± 0.55 mm, respectively. No statistically significant differences in MIC visibility were found across age groups or between edentulous and dentate patients. Mean distances from the MIC’s superior border to the apices of premolars, canines, and incisors were 6.46 mm, 7.10 mm, and 8.99 mm, respectively. Mean distances from the MIC’s buccal cortical border to the buccal alveolar bone plate, from its inferior border to the mandibular inferior border, and from its lingual cortical border to the lingual alveolar bone plate were 2.60 mm, 8.72 mm, and 4.53 mm, respectively. A branch canal was observed in 79.5% of cases, with the MIC showing a downward direction in 64.8% and terminating at the canine apex in 58% of cases. Based on this study’s findings, due to anatomical differences in the mandibular incisive canal, careful evaluation of CBCT images is recommended before surgical procedures in the mandibular interforaminal region, to prevent damage to neurovascular bundles.