“…For SEM analysis (Jeol T330 A, Jeol Ltd., Peabody, MA, USA), the samples were dehydrated in ethanol solutions (Merck, Darmstadt, Germany) of increasing concentrations (30, 50, 70, 80, 95 and 100%), dried overnight in a dehydration jar (Corning, São Paulo, SP, Brazil), mounted on metallic stubs (Senai, Araraquara, SP, Brazil) and sputter-coated with gold. Two photomicrographs were obtained from the center of each sample, with magnifications of 750 and 1,500 X, that were subsequently assessed by an examiner previously calibrated and blind to the experimental groups using the index of smear layer removal 7,12 : Score 1 -Complete removal of the smear layer, dentinal tubules open. Score 2 -Partial removal of the smear layer, dentinal tubules partially open.…”