Comparative Evaluation Of The Shaping Ability Of Four Nickel-titanium Instruments In Simulated Curved Canals

Objective:The aim of this study was to compare the shaping ability of four different Ni-Ti rotary instruments by preparing the simulated resin curved root canals.Methods: Forty simulated resin blocks with curved root canals were randomly divided into four groups(n=10),and prepared using Pro Taper Universal(group A)、iRaCe(group B)、 Reciproc Blue(group C)and HyFlex EDM(group D)respectively.The preparation time was recorded.Images of Pre-and post-instrumentation photograghs were taken by precise camera and superimposed through Adobe Photoshop CS5.The amount of resin removed were measured with Image Pro Plus6.0,and then calculated the center location ability.The data were analyzed by SPSS 17.0 for Statistics analysis.Results: The preparation time of the group B was the shortest(P<0.05).None of the instrument was fractured in the four groups.In the apical area,group B turned out to have the best centering ability;at the curved part,group B and group D both showed a higher centering ability than group A and group C;at the straight part,group B、C and group D were showed a significantly higher centering ability than group A(P<0.05).Conclusions: In this study,iRaCe 、 Reciproc Blue and HyFlex EDM were more outstanding than Pro Taper Universal in the shaping ability of curved canals.