Anatomical classification and geometric modeling of the lingual canal in the anterior mandible: a cone-beam computed tomography study in a Northern Chinese population.

Purpose: This study aimed to investigate the anatomical variations of the lingual canal in the anterior mandible of the Northern Chinese population using cone-beam computed tomography (CBCT), and to develop a geometric framework that may inform preoperative assessment and provide anatomical reference data for future AI-assisted image analysis and implant planning.

Methods: CBCT images from 200 Northern Chinese individuals were analyzed to assess the number, position, diameter, trajectory, and spatial parameters of the lingual canal. Classification was performed based on the canal's location relative to the genial tubercle: superior (SGT) or inferior (IGT). Additionally, canal convergence with the incisive and mandibular canals was recorded, and geometric relationships between key anatomical landmarks were validated.

Results: The lingual canal detection rate was 100%, with 90.5% located in the anterior mandible, primarily in the midline or between central and lateral incisors. Fifteen morphological types were identified. Canals in the SGT group were longer and wider, while those in the IGT group were shorter and narrower. In our sample, canals appeared to be positioned more inferiorly and exhibited smaller diameters (~ 0.5 mm) compared to data reported in non-Chinese populations. A geometric model was proposed: [Formula: see text]. Convergence with the incisive canal was 13.4%, and with the mandibular canal, 1.81%.

Conclusion: The lingual canal in this population shows anatomical variation and distinct spatial configurations. The proposed geometric model and dataset may support CBCT planning and future AI approaches for detecting and classifying lingual canals.