Efficacy of four different irrigation techniques combined with 60°C 3% sodium hypochlorite and 17% EDTA in smear layer removal

Abstract

BackgroundEfforts to improve the efficacy of smear layer removal by applying irrigant activation at the final irrigation or by elevating the temperature of the irrigant have been reported. However, the combination of such activation protocols with 60°C 3% sodium hypochlorite (NaOCl) has seldom been mentioned. The aim of this study was to compare the efficacy in smear layer removal of four different irrigation techniques combined with 60°C 3% NaOCl and 17% EDTA.MethodsFifty single-rooted teeth were randomly divided into five groups (n = 10) according to the irrigant agitation protocols used during chemomechanical preparation(Dentsply Maillefer, Ballaigues, Switzerland): a side-vented needle group, a ultrasonic irrigation (UI) group, a NaviTip FX group, an EndoActivator group, and a control group (no agitation). After each instrumentation, the root canals were irrigated with 1 mL of 3% NaOCl at 60°C for 1 minute, and after the whole instrumentation, the root canals were rinsed with 1 mL of 17% EDTA for 1 minute. Both NaOCl and EDTA were activated with one of the five irrigation protocols. The efficacy of smear layer removal was scored at the apical, middle and coronal thirds. The Data were statistically analyzed using SAS version 9.2 for Windows (rank sum test for a randomised block design and ANOVA).ResultsNo significant differences among the NaviTip FX group, EndoActivator group and control groups, and each of these groups showed a lower score than that of UI group (P < 0.05). Within each group, all three thirds were ranked in the following order: coronal > middle > apical (P < 0.05). In the coronal third, the NaviTip FX group was better than UI group. In the middle and apical third, the differences were not significant among any of the groups.ConclusionsEven without any activation, the combination of 60°C 3% NaOCl and 17% EDTA could remove the smear layer effectively, similar to NaviTip FX or EndoActivator, and these three protocols were more effective than UI. However, regardless of different types of irrigation technique applied, complete removal of the smear layer was not achieved, particularly in the apical third.

Influence of activation mode and preheating on intracanal irrigant temperature

“…any activation, using 60°C 3% NaOCl and 17% EDTA, the smear layer was removed effectively (26). Values followed by different letters are statistically different (P < 0.05).…”

“…Values followed by different letters are statistically different (P < 0.05). any activation, using 60°C 3% NaOCl and 17% EDTA, the smear layer was removed effectively (26). However, the enhanced efficacy of a preheated-irrigant is limited to the time during which it remains warm into the canal (9).…”

Root Canal Treatment (RCT): From Traditional Endodontic Therapies to Innovating Pulp Regeneration

“…Using traditional root treatment, the various techniques so far used include hand files (mechanical methods), or NaOCl and H 2 O 2 (chemical disinfection). These methods are using alternatively irrigation, and they aim at removing the smear layer [7]. They precede chemical and mechanical enlargement.…”

“…Recrystallization process is associated with the Er:Yag laser. The main canal is easier to penetrate when the available probes removed the smear layer [7,9,10].…”

“…They penetrate into dentinal tubules and are associated with the bacteria located near the border of the tubules. The removal of smear layer is never achieved totally in the apical third with these techniques, and it should be remember that the other protocols so far used remove the smear layer in the coronal and middle third of the root canal [7].…”