Abstract

Background: Effective removal of gutta-percha (GP) in endodontic retreatment is a significant factor to ensure a favorable outcome from failed procedures. The purpose of this study was to evaluate the efficacy of rotary and reciprocating file systems for GP removal from root canal systems, with and without the use of solvent.

Methods: Forty extracted single-rooted human mandibular premolars were prepared and obturated using a single cone technique. Specimens were randomly divided into four groups (n=10): Group 1 (Protaper Universal Retreatment (PUR) + Solvent), Group 2 (PUR without Solvent), Group 3 (Reciproc Blue (RB) + Solvent), and Group 4 (RB without Solvent). After retreatment, teeth were split longitudinally and photographed under a stereomicroscope with x50 magnification. Images were imported to the ImageJ software to measure the residual filling material in cervical, middle, apical thirds and the root canal space. The time to reach working length (WL) and total procedural time were recorded. Data were analysed using the Mann-Whitney test (p<0.05).

Results: RB demonstrated significantly higher cleaning efficacy than PUR across total canal walls (p<0.05) in non-solvent conditions. The addition of solvent leaded to increasing residual material in the middle and apical thirds for both systems (p<0.05). PUR reached the WL and completed the procedure significantly faster than RB in non-solvent conditions (p<0.05). Solvent reduced time to reach WL, but significantly increased total procedural time for both systems.

Conclusion: Reciprocating system provides better canal cleaning efficacy compared to rotary system when used without solvent, though rotary system is more time efficient. Solvent hinders filling material removal by creating a sticky residue that prolongs the procedure and prevents thorough canal cleaning.