Micro-CT Analysis of an Abrasive-expanding System of Oval Canal Debridement Capacity: Laboratory Study

Objective: Biomechanical root canal preparation involves both mechanical instrumentation and endodontic irrigation, aiming to reduce bacterial levels to promote periradicular healing. However, complete removal of biofilm and debris, especially in complex canal morphologies, remains difficult. This study aimed to evaluate, through microcomputed tomography (micro-CT), the use of the XP-Endo Finisher and Tornado Disinfection Kit (TDK) systems during the final agitation of the irrigating solution for the final debridement of oval-shaped canals of lower incisors.
Methods: Thirty-nine extracted human mandibular incisors were instrumented up to size #25/.05 and divided into three groups (n=13) based on the final irrigation system: Conventional irrigation with syringe and needle (CI), XP-Endo Finisher (XPF), and TDK. 40 mL of 2.5% NaOCl was used for each group. Teeth were scanned ex vivo using a micro-CT before instrumentation, after instrumentation, and after irrigation. Three-dimensional root canal models were evaluated for volume, untouched surfaces, and dentin removal. Data were analyzed using repeated-measures ANOVA, t-test, and Tukey tests (p<0.05).
Results: TDK showed a significant difference in total and cervical third compared to CI and XPF regarding volume and dentin removal analysis (p<0.05), with no significant difference in the apical third compared to XPF (p>0.05). TDK had a lower percentage of untouched volume compared to the other systems in the overall analysis (p<0.05) and at all thirds compared to CI (p<0.05).
Conclusion: Supplementary instruments improve root canal debridement compared to conventional irrigation, particularly in smaller apical diameters and oval-shaped canals of lower incisors. TDK offers enhanced wall contact after root canal preparation and is a viable alternative for complementing debridement. (EEJ-2024-10-158)