Evaluation of filling material removal in curved canals after different protocols: an ex vivo study with micro-computed tomography

Abstract

Complete removal of the filling material is essential to the success of endodontic retreatment. However, this step can be challenging due to anatomical difficulties, the nature of the sealer, or operational factors. Aim: To evaluate the efficacy of filling removal using ProDesign R and Reciproc Blue retreatment, with supplementary irrigation step with XP-Endo Finisher R. Materials and Method: Twenty mandibular molar mesial canals were prepared using ProTaper Next, and filled using the single-cone technique (n=10). The fillings were subsequently removed using either ProDesign R (25/0.06) or Reciproc Blue (25/0.08 in the 3 mm from the tip of the file, decreasing towards the cervical, with average taper varying from 0.06 to 0.05 along the instrument). The XP-Endo Finisher R system was used for supplementary cleaning for both systems. Micro-computed tomography was used to assess filling material volume and reduction percentage. The significance level was set at 5% (p< 0.05). Results: It was found that ProDesign R and Reciproc Blue removed 91.2% and 82.7% of the filling material, respectively (p > 0.05), and after use of XP-Endo Finisher R, there was a significant increase in filling removal by 42.7 and 27.7%, respectively. Conclusion: ProDesign R and Reciproc Blue were equally effective, but neither system completely removed the filling material from the mesial canals of mandibular molars.