Innovative ex vivo exploration: A comparative study of novel approaches of root canal filling material removal efficiency

Introduction: Retention of the natural tooth without any symptoms in the oral cavity is one of the prime desires of endodontic treatment. Root canal therapy usually leads to failure when treatment is not up to the mark of acceptable standards. To address these deficiencies, non-surgical endodontic retreatment is the most accepted option with the success rate ranging from 65% to 83%. Forty-five single-rooted mandibular premolars with undeviated canals (as per Schneider's criteria) were obtained and divided further into three groups with 15 specimens along with resin-based sealer solvent in each group: Group 1 - Retreatment rotary file system, Group 2 - Ultrasonics, and Group 3 - Diode laser. Specimens were then evaluated under a stereomicroscope at ×10 after cutting in two halves followed by evaluation of the remaining filling material using Hulsmann and Bluhm criteria. Context: Nonsurgical retreatment. Aims: The aim of the study was to evaluate and compare the efficacy of various retreatment techniques for the elimination of root canal filling material. Settings and Design: experimental study. Subjects and Methods: A sum of 45 single-rooted extracted human permanent mandibular premolars were included in this study. All teeth were biomechanically prepared and obturated followed by decoronating the samples. All specimens were randomly divided into 3 groups comprising 15 specimens along with solvent based on the technique for the filling material elimination from the root canal, i.e. Group I: retreatment rotary files, Group II: ultrasonics, and Group III: diode laser. Statistical Analysis Used: tests and one-way analysis of variance were used for comparison of the study parameters among the groups. Results: Results revealed that ultrasonics showed the least amount of remaining filling material within the root canal which had a significant difference from other groups, i.e. retreatment rotary files and diode laser. Conclusions: Ultrasonics with a resin-based sealer solvent can be considered a preferred option for nonsurgical retreatment. However, none of the groups shows complete elimination of filling material inside the root canal system.