Purpose: To investigate the root canal morphology of mandibular incisors using cone-beam computed tomography (CBCT).
Materials and methods: A total of 353 patients with 1,412 healthy, well-developed mandibular incisors were enrolled. Radiographic examination by CBCT was conducted as part of their routine examination, diagnosis and treatment planning. The following observations were made using CBCT: (1) the number of roots; (2) the number of canals; (3) canal configuration according to Vertucci's classification; (4) the position of root canal bifurcations.
Results: Two canals were found in 10.9 % of mandibular central incisors, 25.5 % of lateral incisors and in 18.2 % of all the 1,412 mandibular incisors. Significantly, more lateral incisors possessed two canals than central incisors (p < 0.05). Of the teeth with two canals, type III incisors were the most prevalent, followed by types II, IV and V. Furthermore, 37.7 % of teeth were found to have root canal bifurcations that were at or near to the cortical-middle third junction regions of the roots.
Conclusion: Routine mode CBCT imaging was clinically useful for detection of two canals and determines the position of root canal bifurcations in mandibular incisors.