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.