Effectiveness of different activated irrigation techniques on debris and smear layer removal from curved root canals: a SEM evaluation

Abstract

This study evaluates the effectiveness of different activated irrigation techniques on removal of debris and smear layer from curved root canals. Ninety mandibular molars with a root canal curvature between 20 and 40 degrees were assigned to 4 groups (n = 20): syringe irrigation (SI), passive ultrasonic activation (PUI), sonic activation with EDDY (ED) or EndoActivator (EA) and a control group. Mesiobuccal root canals were prepared to size 40, 0.04 and irrigated with NaOCl (3%) according to the respective technique. Roots were split longitudinally and subjected to scanning electron microscopic analysis. Presence of debris and smear layer was evaluated using 5-grade scoring systems with 2009 and 10009 magnification, respectively. Data were analysed with nonparametric analysis for ordinal longitudinal data (a = 5%). Activation of the irrigant significantly improved smear layer removal (P < 0.05). Regarding debris, only activation with EA and ED was significantly more effective than SI (P < 0.05). No activation technique was able to eliminate debris and smear layer completely from curved root canals.

Efficacy of New Root Canal Irrigant Activation Systems on Removal of Smear Layer

“…In this study, Xp endo finisher and Eddy showed less remaining smear layer at the apical part because of their action in disruption of the apical vapour lock, also continuous rotation of XP-endo finisher and acoustic streaming created by Eddy caused more flow of the irrigating solution scrubbing the smear layer and removing it. (11,24,25) Under the conditions of the current study, it can be concluded that using an activation method as XP endo finisher or Eddy with the irrigating solution, improves the removal of smear layer. Both of them succeeded in obtaining more clean root canal surface than the traditional syringe irrigation method alone.…”

“…It helps penetration of the irrigant to the inaccessible areas and apical third of the canal to clean it and help removal of the smear layer. (11,25) In this study both Xp endo finisher and Eddy improved the action of irrigating solutions on removal of smear layer specially at the middle and apical thirds of the canal in comparison to the traditional syringe irrigation without activation, where the irrigant couldn't completely remove smear layer specially at the apical third of the canals. (11,22,25) Regardless the use of irrigant activation method or not, it is evident that the amount of smear layer remaining at the coronal third was less than that at the middle and apical thirds in all groups.…”

“…(11,25) In this study both Xp endo finisher and Eddy improved the action of irrigating solutions on removal of smear layer specially at the middle and apical thirds of the canal in comparison to the traditional syringe irrigation without activation, where the irrigant couldn't completely remove smear layer specially at the apical third of the canals. (11,22,25) Regardless the use of irrigant activation method or not, it is evident that the amount of smear layer remaining at the coronal third was less than that at the middle and apical thirds in all groups. It was found that the amount of smear layer remaining after mechanical preparation increases as we go more apical in all groups, this could be due to the decrease in root canal diameter at the apical third than the coronal third and less flow of the irrigating solution at the apical part than the coronal, so the root canal wall was subjected to less amount of irrigating solution.…”

Die mechanische Aktivierung von Wurzelkanal-Spüllösungen – eine Literaturübersicht

“…Die Aktivierung der Spüllösung führte im apika-len Bereich zu einer tieferen Penetration der Spüllösung in die Dentintubuli als bei der manuellen Irrigation [20]. Vorteilhaft erscheint der flexible EDDY vor allem bei der Anwendung in gekrümmten Wurzelkanälen zu sein, wo er sich bei der Entfernung von Schmierschicht und Debris der PUI überlegen zeigte [21]. Auch bei der Entfernung von Kalziumhydroxid, das als medikamentöse Einlage verwendet wurde, erwies sich der EDDY als der manuellen Spülung überlegen und der PUI vergleichbar [12].…”

“…Bei der Entfernung von Smear Layer unterschied sich der Endo-Activator allerdings nicht von der manuellen Irrigation [8]. In gekrümmten Kanälen zeigte sich der Endo-Activator der manuellen Irrigation und der PUI in Bezug auf Smear-Layer-und Debris-Entfernung überlegen [21]. Die Auflösung von organischem Gewebe war bei Verwendung des EndoActivator besser als bei der manuellen Spülung und mit EDDY und PUI vergleichbar [19].…”