Cone Beam Computed Tomography Assessment of the Relationship Between Impacted Mandibular Third Molars and the Inferior Alveolar Canal: A Retrospective Cohort Study

Abstract

Aim: This study aimed to identify radiographic indicators of the relationship between impacted mandibular third molar roots and the inferior alveolar canal (IAC) using cone-beam computed tomography (CBCT).

Methods and materials: CBCT scans of 76 adult patients requiring surgical extraction of impacted mandibular third molars were retrospectively collected from the Kamineni Institute of Dental Sciences, Nalgonda. Data were retrieved from electronic health records (October 2023–April 2024). A convenience sample was selected using non-probability sampling and categorized by gender and age groups: 20–30, 31–40, 41–50, 51–60, and 61–70 years. CBCT scans were evaluated for five parameters: (1) direct contact between the IAC and roots, (2) distance between the IAC and roots, (3) cortication of the IAC, (4) IAC position, and (5) IAC shape. Data analysis was conducted using SPSS version 24.0, with Chi-square or Fisher’s exact tests to evaluate associations.

Results: Significant gender differences were observed in the mean contact and distance between the IAC and the root, whereas age differences were significant only for the distance. Other parameters, including the position, shape, and cortication of the IAC, showed no significant differences with respect to age or gender.

Conclusion: These findings highlight the importance of considering individual anatomical variations when planning surgical extractions of impacted mandibular third molars to reduce the risk of injury to the inferior alveolar nerve.