Micro-computed tomographic analysis of the root canal morphology of mandibular incisors

This study aimed to describe the anatomy of mandibular central and lateral incisors using micro-computed tomographic imaging.

One hundred mandibular incisors were scanned in a micro-computed tomographic device using an isotropic resolution of 22.9 μm. The anatomy of each tooth (length of the roots, presence and location of accessory canals and apical deltas, and number of canals) as well as the 2- and 3-dimensional morphologic aspects of the canal (area, roundness, diameter, volume, surface area, and structure model index) were evaluated. Data were statistically compared using the Student t test (alpha = 0.05).

The mean lengths of the mandibular central and lateral incisors were 20.71 and 21.56 mm, respectively. Most of the central (60%) and lateral (74%) incisors had no accessory canals. An apical delta was observed in only 1 specimen. The cross-section analysis of the apical third showed the presence of 1, 2, or 3 canal orifices. No statistical difference was observed in the comparison of the 2- and 3-dimensional morphologic parameters between central and lateral incisors (P < .05). The qualitative analyses of the 3-dimensional models of the root canal systems of the central and lateral incisor teeth confirm that the most prevalent configurations were Vertucci's types I (50% and 62%, respectively) and III (28%).

Overall, mandibular central and lateral incisors were similar in terms of the 2- and 3-dimensional analyzed parameters. Vertucci's types I and III were the most prevalent canal configurations of the mandibular incisors; however, 8 new types have also been described.