Root canal volume, canal transportation and centering ability of protaper next, protaper gold, waveone gold, and reciproc blue using micro- computed tomography 3D modelling analysis

Abstract

Effective root canal instrumentation during endodontic treatment allows for the delivery of the irrigation solution for disinfection and the prevention of apical canal transportation for a better endodontic treatment outcome. The new generation of nickeltitanium (NiTi) endodontic files has better metallurgy properties than conventional NiTi files but less data on root canal shaping efficiency. The objective of this study was to measure the volume changes in the root canal space, the apical canal transportation, and the centering ability of four types of NiTi endodontic files on the mandibular premolar teeth using micro-computed tomographic (micro-CT) imaging. Forty extracted human mandibular premolars with a single-canal and straight root were assigned to four experimental groups (n = 10), in each of which one of the following instrumentation systems was used: ProTaper Next (PTN), ProTaper Gold (PTG), WaveOne Gold (WOG) and Reciproc Blue (RCB). The samples were scanned using high-resolution (9μm) micro-CT imaging before and after the root canal preparation. The samples were prepared to file size #25. The micro-CT images were used to measure the volumetric changes and the mesial and distal dentin thicknesses at 1mm, 3mm and 5mm locations from the root apex to calculate the apical canal transportation and the file centering ability. The data were analysed using parametric and non-parametric tests. The root canal volume significantly differed before and after the root canal preparation. However, regardless of the system or kinematic motion, there was no significant difference in the root canal volume gain across all tested files. There was apical canal transportation and a lack of file centralisation in all files, but it was not statistically significant. PTN, PTG, WOG, and RCB have similar root canal volume changes, apical canal transportation, and centering ability ratios