Comparison of Time Required by D-RaCe, R-Endo and Mtwo Instruments for Retreatment: An in vitro Study.

Abstract

To evaluate and compare the amount of time required by three rotary NiTi instruments in removing gutta-percha from root canal during retreatment with hand file as control. Eighty human mandibular premolars with single straight root canals were prepared and obturated by cold lateral condensation with gutta-percha and AH Plus sealer. After two weeks, the 80 teeth were divided into one control group and 3 retreatment groups (n = 20 each). Gutta-percha was removed using H-files, the D-RaCe, or the Mtwo or the R-Endo retreatment systems. Retreatment time was calculated using stopwatch. D-RaCe and Mtwo required significantly less time than R-Endo and hand file. Hand file took maximum time, which was significantly slower than all groups. However, D-RaCe and Mtwo retreatment time was statistically insignificant. D-RaCe and Mtwo remove gutta-percha faster than R-Endo and Hand files.