XP Shaper, A Novel Adaptive Core Rotary Instrument: Micro-computed Tomographic Analysis of Its Shaping Abilities.

INTRODUCTION: The aim of this study was to investigate the shaping abilities of the XP Shaper (FKG, La Chaux-de-Fonds, Switzerland) and compare the findings with Vortex Blue (Dentsply Tulsa Dental Specialties, Tulsa, OK) using micro-computed tomographic imaging.

METHODS: Twenty matched, extracted, mandibular, central incisors with a single, oval canal were scanned preoperatively at 25-μm resolution and postoperatively after instrumentation with either Vortex Blue in a crown-down manner up to size 30.04 or XP Shaper. The percent of untouched walls, changes in canal volume and surface area, the amount of dentin removed, debris remaining in the canal, and the preparation taper were determined. The total time required for instrumentation using each technique was calculated in seconds. Statistical analysis was used to compare between both groups using repeated measures multivariate analysis of variance with Bonferroni correction for post hoc comparison and independent sample t tests.

RESULTS: The XP Shaper significantly increased the canal volume (F = 77.948, P < .001), surface area (F = 5.543, P = .030), and amount of dentin removed (F = 10.044, P = .001) and had significantly less untouched walls (38.6% ± 8.1%) compared with VB (58.8% ± 8.5%). There was less debris at all levels of the canal in the XP Shaper group. Results were almost significant (P = .059). The XP Shaper was also significantly faster in completing the mechanical preparation of the root canal space by almost 1 minute (t = 6.216, P < .001).

CONCLUSIONS: The XP Shaper can expand beyond its core size to adapt to the anatomy of the root canal space. The XP Shaper can prepare and touch more canal walls in oval-shaped canals compared with Vortex Blue. However, the final preparation taper will vary according to the anatomy of the treated tooth.