Understanding nanofluidic behaviours in energetically unfavourable confining environments is essential for the development of high-performance nanoporous energy absorption systems. In the current study, the effect of liquid composition on defiltration in a hydrophobic nanoporous silica gel is investigated experimentally using two types of admixtures: carbamide of a relatively small molecular si...

introdouction: bleaching has become a common treatment for improving the appearance of natural teeth. however, the need to protect dental restorations from bleaching agent exposure is inevitable, as these agents may change the color of restorative materials by oxidation. filtek p90 composite resin has recently been introduced with the aim of decreasing polymerization shrinkage. the purpose of t...

Objective To compare and evaluate the efficacy of tooth bleaching with prior application two different desensitizing agents such as sodium fluoride 5% potassium nitrate. Materials methods A total 108 extracted human maxillary central incisors were stained in black coffee solution stored artificial saliva for colour stabilization. The specimens randomly divided into three groups (n = 36) accordi...

OBJECTIVES This study aimed to measure pH changes during 14 days intracoronal bleaching with hydrogen peroxide/sodium perborate and carbamide peroxide/sodium perborate. MATERIALS AND METHODS Twenty patients presenting endodontically treated central maxillary incisors with color alterations were divided in two groups (n = 10): Group CP + SP: 37% carbamide peroxide + sodium perborate paste; Gro...

BACKGROUND Different concentrations of carbamide peroxide (10 to 22 percent) have been used successfully as bleaching agents, but the adverse effects on enamel microhardness at different times are unknown. METHODS The authors analyzed seven bleaching agents and a placebo. The agents were applied on the surface of human dental fragments for eight hours per day for 42 days and stored in vials c...

OBJECTIVES This in vitro study evaluated the effectiveness of three carbamide peroxide concentrations used for tooth bleaching treatments. MATERIAL AND METHODS Sixty bovine dental slabs (6x6x3 mm) were obtained, sequentially polished, submitted to artificial staining (baseline) and randomized into four groups (n=15), according to the bleaching agent concentration: distilled water (control), 1...

Although there are several case reports of vital tooth bleaching in children, there is limited clinical trial evidence of the safety or efficacy of this practice. Accordingly, a new clinical trial was conducted to evaluate the effects of 2 different bleaching systems, a 6.5% hydrogen peroxide strip system and a 10% carbamide peroxide tray system, in a population of preteens and teens. A total o...

BACKGROUND Non vital bleaching is simple, conservative procedure for esthetic correction of discolored endodontically treated teeth. The aim of this study was to determine and compare the amount of peroxide leakage from four different bleaching agents i.e superoxol, sodium perborate, combination of superoxol & sodium perborate and carbamide peroxide during intracoronal bleaching, as the safe an...