Apical Root Canal Morphology of Mesial Roots of Mandibular First Molar Teeth With Vertucci Type II Configuration by Means of Micro–Computed Tomography

Abstract

Introduction The aim of this study was to assess the features of the apical root canal anatomy and its relation to the level at which 2 separate root canals merge in the mesial roots of the mandibular first molars with Vertucci type II canal configuration by using micro–computed tomography analysis. Methods The anatomic features of the apical 3 mm of root canals in 83 mesial roots of mandibular first molar teeth were investigated by micro–computed tomography and software imaging according to the level at which 2 separate root canals merge. The most apical slice where a visible root canal was detectable was recorded as 0 level. The specimens from where 2 root canals rejoin at within 3 mm from the 0 level were then assigned to group 1 (n = 37), whereas the specimens from where root canals rejoin 3–9 mm from the 0 level were assigned to group 2 (n = 46). Data were presented by using descriptive statistics and Mann-Whitney U tests, with the significance level set at 5%. Results In all specimens the long oval type of cross-sectional shape increased from 50.9% at 1 mm to 80.5% at 3 mm. Group 1 presented significantly higher major diameter values compared with group 2 (P < .05). There was no significant difference regarding minor diameter values (P > .05) between groups. Group 2 displayed significantly higher roundness values than group 1 (P < .05). Conclusions A long oval root cross section of apical root canal anatomy is more prevalent in roots for which 2 root canals merge within apical 3 mm of root canals. © 2016 American Association of Endodontists