Comparative Evaluation of the Efficacy of Different Ni-Ti Rotary Instruments in Removal of Gutta-Percha During Root Canal Retreatment: An in vitro Study

Abstract

An assessment and comparison of three retreatment files was conducted to determine their effectiveness in the retrieval of gutta-percha. In the investigation, 60 extracted single-rooted human teeth having straight canals and complete apices were used. The ProTaper Universal file system was used to prepare teeth and obturated using gutta-percha with sealant AH Plus utilizing down pack and backfill obturation technique. Removal was performed with ProTaper, D-RaCe files, MTwo, and R-Endo retreatment files. Using a stopwatch, the time needed to take out the GP was also calculated in seconds. We used ANOVA along with the post hoc Tukey’s test to analyze the quantity of obturating material in apical, middle, and coronal third following decoronation and longitudinal splitting. The average percentage of gutta-percha points removed across root levels varied significantly among the ProTaper, D-RaCe MTwo, and R-Endo groups. With the exception of the ProTaper group, when the middle level displayed the most removal, the coronal level showed much higher removal than the mid-root level, while the apical level often exhibited the highest removal. ProTaper retreatment files outperformed MTwo, D-RaCe, and R-Endo among the four groups in terms of removing root canal filling material. However, none of the experimental groups removed gutta-percha completely from root canals.