Morphometric Analysis of Mandibular Canal Variations Using CBCT andIts Clinical Implications in Implant Dentistry: A Cross-Sectional Study
Keywords:
mandibular canal; cone-beam computed tomography; dental implants; anterior loop; bifid mandibular canal; inferior alveolar nerve.Abstract
Background Precise three-dimensional assessment of the mandibular canal is essential before posterior mandibular implant placement because variations in canal course, terminal branching, and proximity to the alveolar crest may increase the risk of inferior alveolar nerve injury. Methods This cross-sectional cone-beam computed tomography (CBCT) study evaluated 240 mandibular scans of adults aged 20-70 years. Bilateral measurements were made at the second premolar, first molar, and second molar regions. Canal-to-crest distance, canalto- buccal cortex distance, canal diameter, anterior loop length, bifid canal prevalence, and implant-related risk zones were recorded. Interobserver reliability was assessed using intraclass correlation coefficients. Results The mean age was 42.8 ± 12.6 years, with 126 males (52.5%) and 114 females (47.5%). Mean canal-to-crest distance reduced posteriorly from 17.64 ± 2.92 mm at the second premolar to 13.21 ± 2.76 mm at the second molar (p<0.001). The mandibular canal was positioned significantly closer to the buccal cortex in the second molar region (4.18 ± 1.06 mm) than in the premolar region (5.62 ± 1.21 mm; p<0.001). An anterior loop was detected in 34.6% of patients, with a mean length of 2.36 ± 0.91 mm. Bifid mandibular canal was observed in 14.2% of patients, most commonly the retromolar type. High-risk implant zones, defined as canal-to-crest distance <10 mm or anterior loop >3 mm, were identified in 19.6% of scans. Conclusion CBCT demonstrated clinically relevant mandibular canal variations that may alter implant length, angulation, and safety margins. Routine preoperative CBCT interpretation should include systematic mapping of the canal, anterior loop, and accessory branches before implant surgery.
Bangladesh Journal of Medical Science Vol. 25. Supplementary Issue-2 (2026), Page : S290-S296
0
0
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2026 Hamzah Ali Babkair

This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish in the Bangladesh Journal of Medical Science agree to the following terms that:
- Authors retain copyright and grant Bangladesh Journal of Medical Science the right of first publication of the work.

Articles in Bangladesh Journal of Medical Science are licensed under a Creative Commons Attribution 4.0 International License CC BY-4.0.This license permits use, distribution and reproduction in any medium, provided the original work is properly cited.- Authors are able to enter into separate, additional contractual arrangements for the distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted to post their work online (e.g., in institutional repositories or on their website) as it can lead to productive exchanges, as well as greater citation of published work.