Comparative Assessment of the Effect of a Modified Irrigation Protocol on the Cleanliness of Moderately Curved Root canals: An In-vitro Study

Authors: Gaurav Jain, Preeti Shukla, Pradyumna Misra, Shronika Shronika, Swadhinta Raj, Anupama Keerikkadu

DOI: 10.18231/j.ijce.12524.1758946730

Keywords: Curved root canals, EDTA, Irrigants, NaOCl, Smear layer

Abstract: Background: Adequate disinfection of root canal system is essential for the success of endodontic therapy and chemo-mechanical preparation of the root canal system during root canal treatment ensures the same. The varying anatomical complexities of root canal is one of the limiting factors for mechanical instrumentation of the canal alone, so judicious use of chemical irrigation assumes more responsibility in such cases. The present study assesses and compares the efficacy of modified irrigation protocols on the debridement and smear layer removal in moderately curved canals, and also its subsequent effect on chemical composition of root canal dentin. Materials & Methods: 60 human single rooted teeth with moderately curved canals (10-30° curvature) were randomly divided into 3 groups (n=20). Irrigation protocol employed in Group I was 5ml of 3% NaOCl between each instrument, followed by 5ml of 17% EDTA for 30 seconds. Group II employed Reverse Irrigation (RI) protocol wherein 5ml of 17% EDTA was used between each instrument followed by 5ml of 3% NaOCl for 30 seconds. In Group III, Reverse Irrigation plus (RI+) was used which is similar to RI except that NaOCl used was agitated manually in the canals. Debridement of root canal dentin was assessed using Scanning Electron Microscope and the chemical composition of dentin was assessed by energy dispersive X-ray (EDX). Results: The mean Hulsmann score at the middle third in all groups were comparable, wherein Group I at 1.8, in Group II at 2.9 while in Group III it was 1.5. At the apical third, the score in Group I was 2.5, Group II was 3.6 and Group II was at 1.5. The difference was significant (p<0.05). The atomic percentage of phosphorus, carbon, oxygen, sodium and magnesium in all groups was comparable. Conclusion: Results showed that 17% EDTA during cleaning and shaping followed by 3% NaOCl rinse for 3 minutes and manual agitation for 30 seconds improved apical debridement in moderately curved canals without inducing dentin erosion.