Evaluation of the efficiency of XP-endo Finisher rotary file in the removalof residual Gutta-Percha and sealer in the retreated root canals by D-Racesystem: invitro study

 The success of the rehabilitation of the orthogonoid depends on the cleansing and adequate formation of the intact areas of the root canal system. For better removal of root canal fill materials, various methods and methods have been proposed, including manual files, ultrasonic instruments, lasers, rotary instruments NiTi. D-Race as one of the widely used instrument provides a twisted-shaped design when visualized by using light microscopes. In this experimental study, 45 adult single-channel premolar teeth with adult roots were collected and kept for two years. The teeth were disinfected by using 2.5% hypochlorite for one hour. The crown of the teeth were cut to CEJ by high speed diamond milling under water flow. The roots were cut to a length of 15mm and the samples were randomly distributed into three groups: 1- XP-F rotary file alone, 2- XP-F rotary file along with NaOCl, 3- XP-F rotary file with chlorohexidine. The study revealed a positive effect of solvent on removal of gutta-percha and sealer in the D-Race systems while, there were no significant differences in NaOCl and chlorohexidine in removing residual gutta-percha or sealer. Moreover, the results showed that the amount of residual gutta-percha or sealer in the middle (M) and coronal (C) slices is significantly lower than that of apical (A) slice. The results showed that XP-F rotary is an efficient retreatment files for removing residual gutta-percha and sealer.