Aim: To compare the effectiveness of R-Endo and E3-ReRoot retreatment rotary files in filling material removal and operating time.
Materials and Methods: Twenty extracted distobuccal roots of maxillary first molars were decoronated to a standard length of 12 mm. Root canal preparations were done using Fanta Blue (Fanta; ShangHai, China) till 0.04/25. Matching gutta percha cones of 0.04/25 were used with Adseal resin sealer (Meta Biomed, Chungcheongbuk-do, Republic of Korea) in warm vertical compaction technique. Teeth were left in an incubator at 37 °C and 100% humidity for 30 days. Cone beam computed tomographic images of all roots were obtained to confirm three-dimensional filling of the root canal space. Roots were divided into two groups according to the file used in retreatment; group A using R-Endo (Micro-Mega, Besancon, France) and group B using E3-ReRoot (IMD; ShangHai, China). Time required to remove the filling material was recorded in seconds. Teeth were then split into two halves using hammer and chisel and remaining filling material was calculated using stereomicroscope at 4X original magnification. Statistical analysis was performed using One-Way ANOVA and significance level was set at 0.05.
Results: E3-ReRoot was shown to be significantly more effective than R-Endo in intracanal filling removal. No significant difference was shown between both systems in the time needed to reach the working length.
Conclusion: E3-ReRoot was more effective in intracanal filling removal although both systems failed to totally remove gutta percha and sealer remnants from the root canals.