Both clinicians and researchers raised suspicions about the potential erosive effects of bleaching on enamel surfaces. The purpose of this in vitro study was to evaluate the effects of bleaching agents containing 35% hydrogen peroxide on the micromorphology of human enamel. Eight intact mandibular incisors were included in the study. Six of them were bleached and two were acid-etched on their vestibular surface. They were analyzed with SEM before and after bleaching with 35% hydrogen peroxide. The bleaching procedure was repeated 2, 4, 6 times, following the manufacturer’s instructions. Two incisors were etched with 37% phosphoric acid for 60 seconds and then submitted to SEM analysis. The acid-etched enamel surfaces showed the typical honey comb aspect and increased surface roughness. The bleached enamel surfaces revealed no such structure and were smooth. Under the circumstances of the current study, bleaching caused no significant morphological alteration of the enamel surface.
Keywords: tooth bleaching, 35% hydrogen peroxide, SEM, enamel