Efficacy of Ethylenediamine Tetraacetic Acid and Calcium Hydroxide in the Removal of Root Canal Filling During Retreatment

Abstract

Objective: To compare the effect of Ethylenediamine tetraacetic acid (EDTA) and calciumhydroxide [Ca(OH)2] in the removal of root canal filling material during retreatment procedure.Methodology: Eighty extracted, single-rooted human teeth were used. Root canals wereshaped with a crown-down technique using Ni-Ti rotary instruments (ProTaper, DentsplyMaillefer, Switzerland) and filled with a cold lateral condensation method. AH Plus was usedas a sealer. After filling, the teeth were divided into 4 groups and root fillings were removed byProTaper Universal rotary retreatment system. In each group different irrigation anddisinfection protocols were followed; Group I. Sodium hypochlorite (5.25%) + EDTA (17%-1 min.) Group II. Sodium hypochlorite (5.25%) Group III. Sodium hypochlorite (5.25%) +Ca (OH)2 Group IV. Sodium hypochlorite (5.25%) + Ca(OH)2 + EDTA (17%-1 min.).Irrigation with 17% EDTA was performed only before D3-Retreatment instrumentation in allgroups. AutoCAD system was used to detect the amount of residual root canal filling material.The results were statistically analyzed by SPSS (Statistical Package for Social Sciences) forWindows 15.0, one way ANOVA and Tukey's HSD tests. The significance was evaluated atthe level of p<0.05.Results: The amount of the remnant filling material in the root canals retreated in Group I wasless than the amount of the material in Group II (p<0.01) and Group III (p<0.05). There was nosignificant difference observed between the other groups in terms of the quantity of the remnantroot canal filling materials (p>0.05).Conclusions: Irrigating the canals with EDTA enhanced the removal of root canal fillingduring retreatment. However, disinfecting the canals with Ca(OH)2 had no effect in the removalof filling material.