Evaluation of root canal transportation, centering ratio, and remaining dentin thickness associated with ProTaper Next instruments with and without glide path.

INTRODUCTION The purpose of this study was to evaluate and compare the volume of removed dentin, transportation, and centering ability of ProTaper Next (PTN) system with and without glide path preparation by using cone-beam computed tomography (CBCT) imaging. METHODS Sixty mesiobuccal canals of mandibular first molars with curvatures of 25°-35° were divided into 3 experimental groups (n = 20) according to the instrumentation technique as follows: group PG/PTN (glide path was created with ProGlider [PG]) and canals were shaped with PTN system), group PF/PTN (glide path was created with PathFile [PF]) and canals were shaped with PTN system), and group PTN (glide path was not performed and canals were shaped with PTN system only). Canals were scanned before and after instrumentation by using CBCT scanner to evaluate root canal transportation and centering ratio at 3, 5, and 7 mm from the apex and volumetric changes. Data were statistically analyzed, and the significance level was set at P < .05. RESULTS There was no significant difference among the tested groups regarding the volume of removed dentin and centering ratio (P > .05). At 3-mm and 5-mm levels, the PG/PTN group showed a significantly lower mean transportation value among the groups (P < .05). However, at 7-mm level, there was no significant difference in canal transportation among the groups (P > .05). CONCLUSIONS PG/PTN instrumentation method revealed better performance with fewer canal aberrations when compared with instrumentation performed with PF/PTN or PTN only.