The effect of EDTA in 3%, 5%, 10% e 17% concentrations in the removal of the smear layer

Abstract

The success of microbial disinfection of the endodontic space depends on the endodontic instruments, the ancillary chemicalsselected and the technical skills used in the chemical-mechanical preparation. Upon completion of the instrumentation thedeposition on the dentine surface of an organic and inorganic material extract of amorphous aspect, with an irregular andgranular surface known as residual layer, was observed. Aiming at removal of this layer several chemicals, in differentconcentrations and applied in pre-established time intervals were used alone, conjugated or mixed. The objective of this studywas to analyze, in vitro, through scanning electron microscopy, the effect of EDTA in 3%, 5%, 10% and 17% concentrations onthe removal of the residual layer and cleaning of the dentine tubules through applications ranging from 1 to 3 minutes. Eightunits from an 80-tooth sample were randomly selected to compose the negative control set (GC1) and other 8 units to composethe positive control set (GC2). The remaining 64 composed the 8 experimental sets (GExp.). Analysis of the photomicrographsat magnitude 2000X revealed that the 10 % and 17 % EDTA solutions were the most effective irrespective of the pre-establishedapplication times. It was also observed that the apical third showed a lower degree of cleaning than the cervical and basalthirds.