Evaluation of morphological changes produced by orifice opener systems using computerized tomography (CT)

Objectives: To evaluate modifications in root canal morphology following instrumentation with orifice openers using Computerized Tomography (CT). Study design: Experimental in vitro study. A preoperative CT was performed on 49 molars to measure the root canal cross-sections. After preparing the canals with 6 different nickel-titanium (Ni-Ti) rotary system orifice opener type instruments and Gates Glidden burs, a further CT was made and compared with the preoperative one. Kruskal-Wallis and ANOVA statistical analysis were used. Results: Gates Glidden burs were significantly more aggressive in the coronal portion of the canals, although all the instruments removed more dental tissue in the mo…