A comparison of root canal transportation and centering ability between WaveOne® Gold and Protaper Next® files, using microcomputed tomography

Abstract

This study compared the transportation and centering ability of ProTaper Next (PTN) and WaveOne Gold (WOG) files in curved permanent teeth using micro-computed tomography (μCT). Twenty-four molar teeth with curved roots were divided randomly into two equal groups. The root canals of one group was prepared using PTN files, and the other using WOG files. Pre-instrumentation and post-instrumentation μCT imaging were taken for all the teeth. The dentine thickness of the pre-and the post-instrumentation cross sections was measured at eight different points at three levels: 3, 5 and 7mm from the apex, by two dentists using image analysis software. The data were analysed using one-way ANOVA, at a 5% significance level. The transportation in both groups was within the range accepted in the literature. The WOG file exhibited significantly less root canal transportation compared with the PTN file (p=0.001). The WOG file showed a significantly (p<0.001) higher mean centering ratio of 0.4286 when compared to that of PTN at 0.2448. Using a novel technique to measure canal transportation, this study found that the WOG and PTN systems were both suitable for preparation of curved molar root canals, but the WOG showed significantly less canal transportation and better centering ability than the PTN system.