Computed Tomography Assessment of Canal Centering Ability Using Hand and Rotary Instruments-An in Vitro Study

Aim: The present in vitro study aims to evaluate canal preparation comparing centering ability of ProTaper, Mtwo ,Wave One, Hand Ni-Ti K-files using Computed Tomography(CT).
Materials and Methods: Sixty extracted permanent teeth were selected and decoronated at 11 mm from the apical end. Samples were randomly divided into 4 groups as ProTaper, Mtwo,Wave One, Hand Ni-Ti K-files. Teeth were scanned by CT Scanner. Sectioning was started at 1 mm from the apex up to coronal orifice. Nine levels at 1 mm each were chosen for evaluation in the Computed Tomography. The canals were prepared and a post instrumentation scan was again taken. The pre and postoperative CT images were superimposed at all nine levels. The canal centering ability was calculated. Statistical data was evaluated using OneWay Analysis Of Variance test.
Results: Amongst the rotary and reciprocal groups the best canal centering ability at the apical third was seen withWave one. All the three groups behaved similarly in the middle and coronal thirds of the ischolar_main canal.  
Conclusion: Keeping in mind the importance of apical third preparation and consistent behaviour in all directions, Wave One may be considered by far the best in the apical third.