Root canal length measurement of molar teeth using conebeam computed tomography (CBCT): comparison of twodimensional versus three-dimensional methods

Abstract

PurposeThis study aimed to evaluate the validity of 2-dimensional (2D) and 3-dimensional(3D) cone-beam computed tomographic (CBCT) root canal length measurementsof molar teeth compared with actual root canal lengths and the influence of canalcurvature on the accuracy of CBCT measurements.Materials and MethodsSeventy root canals of 24 molar teeth were scanned using CBCT, and the root canalswere categorized as; ‘straight/curved,’ ‘highly curved,’ and ‘multiple curved.’ The 2Dmeasurements were performed within a suitable slice between the major foramenand the corresponding cusp. The 3D measurements were performed within theslices in regular intervals of axial planes in between the same reference points.The reproducibility and reliability of the methods were analyzed by intraclasscorrelation coefficient. Differences between the actual and CBCT root canal lengthswere evaluated by chi-square and McNemar tests if the measurements were withinacceptable limits of ±0.5 mm.ResultsBoth methods were found to be reproducible and presented excellent reliability.However, the 3D method was significantly more accurate, with an 85.7% frequencyof measurements within acceptable limits (p