Retreatment efficacy 3 months after obturation using glass ionomer cement, zinc oxide-eugenol, and epoxy resin sealers

The efficacy of ultrasonic retreatment, 3 months after obturation, in conjunction with Ketac-Endo, Roth's 801, and AH26 sealers was evaluated. Seventy-two root canals were prepared and obturated with gutta-percha and one of the sealers mentioned above. After 90 days, the canals were retreated by an ultrasonic technique and the retreatment time was recorded. The roots were split and the amount of debris that remained on the canal walls in three separate levels was scored. Compared by one-way and two-way analysis of variance, the mean scores of remaining debris at the different canal levels for the three sealer groups, as well as for each group, were not significantly different. The only significant difference was found in retreatment time for which Ketac-Endo was significantly slower to retreat than the other two sealers (p < 0.002). Thus, the results of this study showed that the amount of debris remaining on the root canal walls following retreatment 3 months after obturation is similar for Ketac-Endo, Roth's 801, and AH26 sealers, but the retreatment time for Ketac-Endo is significantly longer.