Comparative evaluation of the efficacy of two distinct irrigation techniques with and without refined orange oil as gutta-percha solvent on the cleanliness of dentinal tubules during endodontic re-treatment: An in vitro, scanning electron microscopic study

Introduction: There is hardly any evidence to comprehend the effect of passive ultrasonic irrigation during endodontic re-treatment, especially when used with or without gutta-percha solvents. The aim of the present study was to assess the impact of refined orange oil as gutta-percha solvent, while to compare passive ultrasonic irrigation with syringe irrigation on the cleanliness of dentinal tubules in endodontic re-treatment cases. Materials and Methods: The present in vitro study included 60 extracted intact human mandibular premolars. Again, canal preparations were done, while the samples were divided into three groups, including a control group (Group 1) wherein the canals were left unobturated ( n = 20), while in Group 2, endodontic re-treatment with refined orange oil solvent ( n = 20) and in Group 3, without refined orange oil was accomplished ( n = 20). Again, Group 2 and Group 3 were divided into two subgroups, wherein in subgroup A ( n = 10), the syringe irrigation technique was used, while in subgroup B ( n = 10), passive ultrasonic irrigation was performed. All the samples were evaluated under scanning electron microscope (SEM) to assess the cleanliness of dentinal tubules. Results: Statistically significant differences were observed between different groups with Group 3 revealing the highest mean values at all levels (coronal – 0.17200, middle – 0.20800, apical – 0.31500), followed by Group 2 and Group 1 ( P < 0.001). Furthermore, subgroups A revealed higher mean values than subgroups B with statistically significant results ( P < 0.05 to P < 0.001). Conclusions: Passive ultrasonic irrigation, when used with refined orange oil solvent, resulted in significantly cleaner dentinal tubules at all levels than the syringe irrigation technique. The following core competencies are addressed in this article: Practice-based learning and improvement, Patient care and procedural skills, Systems-based practice, Medical knowledge.