title: Demineralization effect of EDTA, EGTA, CDTA and citric acid on root dentin: a comparative study.
abstract: The purpose of this study was to biochemically compare the decalcifying effects of 1% EDTA (pH 7.4), 1% EGTA (pH 7.4), 1% CDTA (pH 7.4), 1% citric acid solutions (pH 1.0 and 7.4) and saline solution (control) on root dentin. Forty-eight single-rooted teeth were used in this study. The canals were instrumented by the step-back technique and the roots were randomly divided into six equal experimental groups (n = 8) according to the irrigating agent tested. A total of 30 microL of each solution was pipetted into the root canal and allowed to set undisturbed for 5 minutes. After this time, 15 microL of the solutions were removed from each canal using a Hamilton syringe and placed in a container with 5 mL of deionised water. The microg/mL concentration of calcium ion (Ca2+) extracted from the root canal samples was determined using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Data were analysed by means of the Kruskal-Wallis and Mood's median tests. Citric acid solution at pH 1.0 removed more calcium than at pH 7.4 and than the other chelating solutions tested (p < 0.05). No differences were observed between EDTA and EGTA. Both EDTA and EGTA removed significantly more calcium than CDTA and citric acid at pH 7.4 (p < 0.05). There were no differences between citric acid at pH 7.4 and saline solution, which had the least efficacy for Ca2+ extraction (p > 0.05). These results indicate that citric acid at pH 1.0 is a good alternative as an irrigating solution to remove the smear layer and facilitate the biomechanical procedures.
authors.affiliation: Department of Metallurgy and Material Science, Pontifical Catholic University of Rio de Janeiro.
authors.forename: Simone Maria Galvão de
authors.initials: SM
authors.lastname: Sousa
authors.forename: Thelma Lopes
authors.initials: TL
authors.lastname: Silva
mesh_terms: D002614:Chelating Agents / Q000494:pharmacology*; D019343:Citric Acid / Q000494:pharmacology*; D003804:Dentin / Q000187:drug effects*; D004492:Edetic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D006801:Humans; D017001:Tooth Demineralization / Q000139:chemically induced*; D014092:Tooth Root / Q000187:drug effects*
chemical_list: D002614:Chelating Agents; D019343:Citric Acid; C005390:CDTA; D004533:Egtazic Acid; D004492:Edetic Acid