Abstract
This study investigated the bleaching efficacy of a mixture of sodium hydrogen carbonate (NaHCO3) and 30% hydrogen peroxide (H2O2), the latter being an active ingredient in in-office bleaching products. A commercially available 35% H2O2-based in-office bleaching product was used as a control and for comparison. Enamel surfaces after bleaching were evaluated for post-bleaching color change, Vickers hardness, surface roughness, erosion depth, and surface morphology (SEM images). The bleaching efficacy of 30%H2O2-NaHCO3 was comparable to that of control, and favorable results over the control were obtained after bleaching with 30%H2O2-NaHCO3, lower increase in surface roughness, smaller erosion depth, and reduced extent of enamel erosion based on SEM images. These results were obtained because an addition of NaHCO3 to H2O2 changed the initially low pH to a higher one.
