Canal preparation is a major step in root canal treatment and is directly related to subsequent disinfection and obturation. In recent years, nickel-titanium rotary systems such as the EndoSequence (Brassler USA, Savannah, GA), the ProTaper Universal (Dentsply/Maillefer, Ballagigues, Switzerland), and the ProFile GT (Dentsply/Maillefer, Ballagigues, Switzerland) have significantly altered root canal instrumentation. EndoSequence has become a very popular system among general practitioners but has not been scientifically tested or compared with other rotary systems that are commonly used by both specialists and general practitioners. The purpose of this study was to compare cleaning effectiveness under scanning electron microscopy (SEM) using three different rotary nickel-titanium instruments: the ProTaper variable taper, the ProFile GT .04 taper, and the EndoSequence .04 taper. Thirty-six extracted mandibular molars were selected for this study. The teeth were randomly divided into three groups. Each group had two noninstrumented teeth that served as controls. All teeth were prepared to a #40 final apical file after manufacturers' instructions. All three systems were used in the traditional "crown-down technique." Teeth were sectioned buccolingually and examined under SEM at 20.0 kV and 500x magnification in the middle third of the canal. Debris was defined as dentin chips, pulp remnants, and particles loosely attached to the root canal wall. Analysis of the SEM images was performed by using a five-score index. Results indicated that there was no difference in cleansing ability of the three file types.

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http://dx.doi.org/10.1016/j.joen.2008.09.022DOI Listing

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