Avaliação de diferentes substâncias quelantes na limpeza dos canais radiculares

Abstract

Due to the commercialization of different brands of EDTA, many doubts arise regarding the efficiency in the removal of the smear layer. Objective: To evaluate the cleansing ability of the chelators (cervical, middle and apical thirds) of human teeth. Material and method: Thirty-five (35) human canine roots were used for the study. These roots were divided into four experimental groups, according to the type of substance used in the final cleaning: G1: EDTA 17% Biodynamic, G2: EDTA 17% Iodontosul, G3: EDTA 17% Maquira and G4: Negative control (saline solution). All roots were instrumented with the system of reciprocating limes and irrigated with 1 ml of 2.5% NaOCl at each exchange of lime during the chemical-mechanical preparation. Only in the final cleaning the conduits were flooded with 0.2 ml of test substances from their respective groups for 3 minutes. Afterwards, the teeth were cleaved, analyzed in Scanning Electron Microscopy and photomicrographs. The photomicrographs were classified according to the amount of residual layer of magma found on the walls of the root canal. The data were submitted to non-parametric Kruskal-Wallis statistical tests at a significance level of 5% (a = 0.05). Results: Low efficiency in the removal of smear layer in all groups, and the apical third presented the worst results, since most of the samples obtained scores 4 and 5. Conclusion: None of the chelating agents used were successful in cleaning the root canals.