In Vitro Comparison of TruNatomy and Conventional Needle Irrigation for Root Canal Debris Removal

Background: Effective root canal irrigation plays a crucial role in endodontic success by facilitating debris removal and enhancing disinfection. Conventional Needle Irrigation (CNI) remains widely used despite its limitations in effectively cleaning the apical third. The TruNatomy (TRN) flexible irrigation needle has been introduced as an alternative, designed to improve fluid dynamics and optimize debris removal. This In vitro study aims to compare the efficacy of TRN and CNI in debris removal from simulated root canals. Methods: Thirty-six artificial root canals in resin blocks were randomly divided into two groups (n = 18 each): the conventional needle irrigation group using a 30-G side-vented needle and the TruNatomy group using a flexible irrigation needle. Irrigation was performed with 5 ml 2.5% sodium hypochlorite (NaOCl) for 90 seconds, followed by a final rinse with 17% EDTA for one minute and saline irrigation. Digital imaging was used to quantify debris removal by superimposing a 160-square grid onto post-instrumentation images. Two independent evaluators assessed the debris and Cohen’s kappa statistic (0.82) confirmed interrater reliability. Statistical analysis was conducted using the Mann-Whitney U-test, with significance set at p<0.05. Results: The TruNatomy needle demonstrated significantly better debris removal at 1 mm from the working length compared to conventional needle irrigation. The mean debris percentage in the TRN group was 2.26% (±0.35), whereas the conventional needle group exhibited 5.3% (±0.91) (p<0.001). Additionally, the mean number of debris pixels in the TRN group was significantly lower (10.8±1.7) than in the conventional needle group (25.8±4.3, p<0.001). Conclusions: TruNatomy flexible irrigation needle significantly improved debris removal in simulated root canals, particularly in the apical third, when compared to conventional needle irrigation. However, since this study was conducted using resin blocks, which lack the anatomical complexity of natural root canals, the findings should be interpreted with caution. Further in vivo studies are necessary to validate these results in clinical scenarios and assess the long-term impact of TruNatomy irrigation on endodontic treatment outcomes.