PEREZ DE ARCE, C. V. I.; RODRÍGUEZ, O. P. A. & ECHEVERRI, C. D. Sonic versus ultrasonic activation of 10% EDTA for smear layer removal in the root canal apical third. Int. J. Odontostomat., 8(1):153-159, 2014.
ABSTRACT: The purpose of this study was to observe the effect of passive sonic and ultrasonic irrigation with 10% Ethilenediaminotetracethic acid (EDTA) on smear layer of the apical third of instrumented root canals as well as the level of erosion produced on the canal walls. For this quantitative experimental in vitro study 40 teeth were hand instrumented with step back technique until master file num 55 and divided in four groups according to the final irrigation protocol: I: distilled water without activation, II: 10% EDTA for 30 seconds without activation, III: 10% EDTA sonic activated for 30 seconds, IV: 10% EDTA ultrasonic activated for 30 seconds. Samples were prepared for MEB observation at 5000X. The presence of smear layer and erosion on dentine walls was quantified according to Torabinejad et al. criteria. Data were submitted at Kruskal-Wallis test and Tukey Post Hoc with a significance level of 5% (P=0.05). When evaluating the smear layer presence, there were no statistically significant differences between the groups II, III and IV. Group I had a highest amount of smear layer (p<0.01). As for erosion, group II showed higher erosion than the others, being significant with groups I and III (p=0.006). Among groups I, III and IV there were not statistically significant differences. Sonic and ultrasonic activation of EDTA 10% did not produce a significantly superior removal of smear layer when compared with conventional irrigation. Erosion of root canal walls was significantly lower after sonic activation.
KEY WORDS: EDTA, irrigant activation, passive ultrasonic irrigation, passive sonic irrigation, dentin erosion, smear layer removal.