Effect of Bleaching Agents on the Hardness and Morphology of Enamel

Abstract

Bleaching treatment conducted with two home bleaching agents (Opalescence 10%, Ultradent, and Hi-Lite II, Shofu) had no adverse effects on enamel microhardness or on surface morphology. Bleaching with 3% hydrogen peroxide can have a negative effect on enamel hardness and surface morphology when performed as described in this study.

Hydrogen Peroxide Tooth Whitening Agent Effect on the Nanomechanical Properties of Enamel

“…This is in agreement with several previous reports [29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44]. In contrast, a few studies have reported changes in the mechanical properties of enamel [45,46,47].…”

Effect of Different Fluoridation Regimes on the Microhardness of Bleached Enamel

“…7,9,13,[19][20] However, other studies reported that 10% carbamide peroxide gel did not affect enamel surface hardness. [21][22][23] These contradictory findings among different studies might be due to differences in method, such as frequency and time of bleaching treatment, storage media or the use of human or bovine teeth.…”

Effect of Delaying Toothbrushing During Bleaching on Enamel Surface Roughness: An In Vitro Study

“…9,27,28 However, other studies have reported different results with no statistically significant differences in tooth hard tissue characteristics, including enamel and dentin surface roughness, after bleaching with 10% and 15% carbamide peroxide. 17,18,[29][30][31] The discrepancies in the results of various studies might be attributed to differences in the formulation and concentration of bleaching agents; the duration of daily applications or treatment protocols; differences in study designs, including the environments in which the specimens are stored (eg, artificial or human saliva); the use of remineralizing agents; continuous use of fluoridated toothpastes; and the technique of toothbrushing during the procedure and after bleaching. 2,14,30,32,33 In the present study, tooth structures underwent surface changes after bleaching, and toothbrushing immediately after bleaching had a substantial role in increasing enamel surface roughness.…”