OBJECTIVE The purpose of this in vitro study was to compare the efficacy of a bleaching toothpaste containing Blue Covarine vs. conventional tooth bleaching techniques using peroxides (both in-office and at-home). MATERIAL AND METHODS Samples were randomly distributed into five experimental groups (n=15): C - Control; BC - Bleaching toothpaste containing Blue Covarine; WBC - Bleaching toothpa...

Bleaching detergent formulations contain environmentally unfriendly bleaching agents (perborates and percarbonates), which cause aquatic eutrophication, although without these compounds detergents are much less efficient for the washing processes. In an effort to replace these compounds, in this study, hydrogen peroxide was generated as a bleaching compound by means of enzymatic reactions. Thre...

BACKGROUND Bleaching the discoloured teeth may affect the tooth/composite interface. The aim of this in vitro experimental study was to evaluate the effect of vital tooth bleaching on microleakage of existent class V composite resin restorations bonded with three dental bonding agents. METHODS Class V cavities were prepared on buccal surfaces of 72 intact, extracted human anterior teeth with ...

Bleaching of eumelanin has been studied in model systems consisting of synthetic dopa-melanin and various concentrations of hydrogen peroxide, molecular oxygen, and copper(II) ions at neutral and alkaline pH. The data show that at neutral pH, in the dark, metal-ion-free melanin is very resistant to oxidation by hydrogen peroxide. However, the rate of bleaching of melanin, induced by H2O2 is sig...

OBJECTIVE The purpose of this study was to determine the effect of 10% carbamide peroxide and 38% hydrogen peroxide bleaching agents on the shear bond strength of orthodontic brackets using self-etching primer systems. METHODS Forty five freshly extracted human premolar teeth were randomly divided into 3 groups of 15 teeth each: control (group 1), 10% carbamide peroxide at-home bleached (grou...

Tooth bleaching using peroxide-based materials is an effective procedure in dentistry. Studies provide evidence on the safety of bleaching by dental professionals. However, concerns and controversy remain regarding the safety of bleaching systems that do not involve dental professionals, especially those available at mall kiosks, salons, spas, and cruise ships. Bleaching causes tooth sensitivit...

Tooth whitening is one of the most conservative procedures for increasing aesthetics patients, but effect bleaching on ceramic restorations has not been extensively studied. In this study, three dental restoration materials (polished/glazed lithium disilicate glass ceramic, leucite reinforced and zirconium dioxide ceramic) investigated in terms surface roughness changes exposed samples. Philips...

OBJECTIVES There is still some controversy in the dental literature whether carbamide peroxide bleaching causes demineralization of teeth. One of the reasons for this controversy is that there is as yet no reliable, non-destructive in vitro method for assessing mineral loss in bleached teeth. The objective of this study was to investigate the possible demineralization effect of 10% carbamide pe...

A brightness of 76% (initially 57%) was reached with a charge of 4.5% hydrogen peroxide based on thermomechanical pulp in 10 min with microwave heating, compared to 45 min with water-bath heating. The maximum brightness attained with water-bath heating (78%) was nearly one point higher than that obtained with microwave heating, albeit after twice the time (120 min vs. 60 min). Under similar con...

Two organic deposits accumulated in a Kraft pulp mill during pulping of Eucalyptus globulus wood and throughout a TCF (totally chlorine free) bleaching sequence were characterized. One deposit was collected after cooking and an oxygen delignification stage while the other was collected after bleaching with hydrogen peroxide. The deposits were Soxhlet extracted with acetone, and the extracts red...