Efficacy of three Ni–Ti rotary systems for removal of filling materials from root canal system of extracted teeth

ObjectivesThe aim of the present laboratory study was to evaluate the efficacy of ProTaper Next (PTN) in removing root canal fillings and comparing it with ProTaper Universal (PTU) and ProTaper Retreatment (PTR).MethodsRoot canals in 60 single-rooted teeth were instrumented and obturated with gutta-percha and MTA Fillapex sealer then stored for one week. After that, the samples were divided randomly into three groups according to the instrument used in retreatment. Group 1, retreatment was done using ProTaper Retreatment (PTR), Group 2, retreatment was done using ProTaper Universal (PTU), and Group 3, retreatment was done using ProTaper Next (PTN). The total time required to achieve the end-point of root filling removal was recorded for each sample. Roots were split longitudinally, canals were observed using a stereomicroscope at 10×. The images were subjected to morphometric analysis to assess the amount of remaining root filling material. Statistical analysis was performed by ANOVA and Tukey's honest significance difference post hoc tests were run on the data to determine significant differences between the groups.ResultsPTN showed the shortest time for removal of the root canal filling material followed by PTR then PTU which had the longest time. PTN produced a statistically significantly lower remaining filling material in both middle and apical third when compared to the other two systems. However, both PTU and PTR produced statistically significantly less remaining debris in the coronal third.ConclusionProTaper Next was efficient in removal of gutta-percha and MTA Fillapex root canal sealer.