Lateral Lingual Foramina and Canals in the Mandible: CBCT Evaluation of 506 Patients in North China

Objective: To assess the prevalence, location, diameter, course and anastomosis of the lateral lingual foramina (LLF) and canals (LLCs) in a northern Chinese population using CBCT. Methods: CBCT images of 506 patients (181 male and 325 female, mean age 21.03 +/- 8.11 years) were collected. The prevalence, location, diameter, length, angle and anastomosis of the LLF and LLCs were assessed. The measurement variables were analysed by sex and age. Statistical analysis was performed using SPSS (v. 25, IBM, Armonk, NY, USA). Results: A total of 461 LLF were detected in 307 (60.7%) subjects, 175 (57.0%) of whom had unilateral LLF and 132 (43.0%) of whom had bilateral LLF, with each lateral having one to four LLF. The majority of LLF (375/461, 81.3%) were located below the premolars, particularly the first premolar. The mean diameter of the LLF was 0.58 +/- 0.20 mm. The mean vertical distance from the LLF to the inferior border and the alveolar crest was 6.68 +/- 1.43 mm and 23.65 +/- 2.89 mm, respectively. In total, 197 LLCs were visible in the cancellous bone and evaluated. The mean length of LLCs was 6.26 +/- 1.29 mm, and the mean angle of LLCs was 140.64 degrees +/- 17.29 degrees. The overwhelming majority (93.4%) of LLCs communicated with the mandibular incisive canal and the rest connected with the mandibular canal. Conclusion: The prevalence of LLCs was high in the northern Chinese population. The presence of LLCs is a significant predictor of communication with the mandibular incisive canal.