Canal Transportation and Centering Ability of ProTaperNext versusProTaperUniversal

Abstract

Over the decades, evolutional changes have been introduced for the Ni-Ti rotary files to facilitate the shaping ability for the curved canals; these changes have included the design and the alloy itself. ProTpaer Next is considered to be one of these recently introduced files that have unique features of being with M-Wire technology, variable taper and offset mass of rotation. This study aimed to evaluate the effect of the ProTaper Universal and ProTpaer Next rotary Ni-Ti files regarding the canal centering and canal transportation at different cut levels. Sixty Mesio-buccal canals human mandibular molars were divided into 2 equal groups according to canal curvature that determined by Schneider (1) method pre-operatively into (15-25) and (30-45), then subdivided into 2 equal sub-groups according to the rotary system used (ProTaper Universal and ProTaper Next). The teeth were fixed in position inside a mold of acrylic resin during the whole study and then the teeth were scanned using Cone Beam Computed Tomography before and after instrumentation by the two systems according to the manufacturer’s instructions. Fusion of the pre-instrumentation and post-instrumentation records was achieved using special software that allowed automatic registration of the primary and secondary images. The data obtained by the CBCT was used in the Gambil et al (2) equation to calculate the canal centering and canal transportation occurred at different cut levels. Data were presented as Mean and standard deviation values. Fridman test was used to compare different levels within groups followed by Wilcoxson rank test with Bonferrioni correction. Wilcoxon rank test was used to compare between BL and MD within groups. Mann Whitney test was used to compare between files and curvatures. Summary and Conclusion