The internal root canal morphology of single-rooted mandibular canines revealed by micro-computed tomography

CONTEXT: The lack of thorough knowledge regarding morphological and anatomical variations of the root canal system can result in failure to identify all root canals and lead to inadequate instrumentation and consequent failure of the endodontic treatment. AIMS: The aim of the study was to evaluate the anatomy of single-rooted mandibular canines using micro-computed tomography (micro-CT). SUBJECTS AND METHODS: Eighty mandibular canines were scanned by micro-CT to determine anatomic parameters: Vertucci's classification, number of lateral canals, roundness, and minor and major diameters. The shape of root canal orifices, volume, surface area, and convexity structure model index (SMI) were also evaluated. ANALYSIS USED: The CTAn and CTvol software were used to three-dimensional and morphometric analysis. RESULTS: All canals were classified as Vertucci Type I. Lateral canals were verified in 42.4% of the roots, in apical third. The canal diameters were decreased near the apex. The cross sections at the cementoenamel junction and 1 mm from the apex were oval in 38.3% and 79.4% of the canals, respectively. The mean canal volumes and surface areas were 11.48 ± 4.41 mm(3)≥ and 67.29 ± 19.18 mm(2), respectively. The SMI values indicated that mandibular canine was approximately rod like. CONCLUSIONS: The morphology of the root canal of single-rooted canines varied widely at different root levels.