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Decalcifying effect of EDTA-T, 10% citric acid, and 17% EDTA on root canal dentin
Miriam F Zaccaro Scelza1, Ana Maria Teixeira, Pantaleo Scelza
1Department of Endodontics, Federal University Fluminense, RJ, Brazil.
Objective:
An in vitro study was conducted to determine the efficacy of 17% EDTA plus 1.25% sodium lauryl ether sulfate (EDTA-T), 10% citric acid, and 17% EDTA with respect to Ca(++) extraction.
Study Design:
The root canals of 90 extracted human canines were instrumented by using the step-back technique. The teeth were randomly divided into 9 groups of 10 teeth each according to the solution and time intervals involved (ie, 3, 10, and 15 minutes). The Ca(++) concentration of the solution was determined by using atomic absorption spectroscopy.
Results:
At 3 minutes, there was no significant difference between Ca(++) extraction by 10% citric acid and 17% EDTA (P >.05). EDTA-T had the least efficacy for Ca(++) extraction (P <.05). At 10 minutes and 15 minutes, there were no significant differences between 10% citric acid and 17% EDTA or between EDTA-T and 17% EDTA (P >.05). However, 10% citric acid was significantly better than EDTA-T in terms of Ca(++) extraction (P <.05).
Conclusion:
Both 10% citric acid and 17% EDTA are good decalcifying agents when the step-back technique is used.
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