Various studies have reported a significant reduction in tensile bond strength of brackets when bonding is carried out immediately after bleaching. The purpose of this investigation was to determine the effect of an antioxidant agent on the tensile bond strength values of metal brackets bonded with composite resin to human enamel after bleaching with carbamide peroxide (CP). A total of 80 extra...

Light and heat increase the reactivity of hydrogen peroxide. There is no evidence that light activation (power bleaching with high-intensity light) results in a more effective bleaching with a longer lasting effect with high concentrated hydrogen peroxide bleaching gels. Laser light differs from conventional light as it requires a laser-target interaction. The interaction takes place in the fir...

Reef corals are sentinels for the adverse effects of rapid global warming on the planet's ecosystems. Warming sea surface temperatures have led to frequent episodes of bleaching and mortality among corals that depend on endosymbiotic micro-algae (Symbiodinium) for their survival. However, our understanding of the ecological and evolutionary response of corals to episodes of thermal stress remai...

Ozone is a non-chlorine bleaching agent that can reduce pollution in the pulp bleaching stage. In this work the ozone bleaching of eucalyptus kraft pulp was performed as part of a kinetics study to explain factors affecting the properties of bleached pulp. The bleaching efficiency was closely related to the rates of mass transfer and self-decomposition, as well as the intensity of ozonation. Fo...

Recent dramatic bleaching events on coral reefs have enhanced the need for global environmental monitoring. This paper investigates the value of present high spatial resolution satellites to detect coral bleaching using a change detection technique. We compared an IRS LISS-III image taken during the 1998 bleaching event in Belize to images taken before the bleaching event. The sensitivity of th...

Sickle cell disease (SCD) is a monogenic disease that affects millions of people worldwide. This study analyzed the effectiveness of bleaching and tooth sensitivity after in-office bleaching in patients with SCD. Forty volunteers were randomly assigned to four groups of 10 patients each (five with the SCD and five healthy controls) and treated using in-office bleaching with 35% hydrogen peroxid...

Background and Aim: Bleaching agents differently affect the color of composite restorations. This study aimed to assess the effect of two different bleaching agents on color change of silorane-based and two types of methacrylate-based composites. Materials and Methods: This in-vitro study was conducted on 18 disc-shaped specimens measuring 10×2mm made of A3 shade of Z250, Z350 and P90 composite...

Introduction: Internal bleaching is a treatment option for wightening endodontically treated discolored teeth. Cervical resorption is one of the side effects of this method.The aim of this study was to compare the sealing ability of resin composite and light-cured resin modified glass ionomer (RMGI) as intra-orifice barriers in internal bleaching. Materials &Methods: In this study, 34 single...

Coral bleaching spread across the southern Great Barrier Reef in January 2006, after sea temperatures reached climatological summer maxima 2 months before normal. Current satellite-derived warning systems were unable to detect severe bleaching conditions in the region because of their use of a constant thermal threshold (summer maximum monthly mean) and low spatial resolution (50 km). Here it i...

OBJECTIVE The aim of the present study was to assess the hypothesis that the efficiency of vital tooth bleaching depends on the concentration of carbamide peroxide agents. METHODS The front teeth of 30 subjects were bleached at home with 10%, 17% or 0% (control) carbamide peroxide for 1 week in a double-blind study design. Tooth shades were determined in the LCH color space employing a visual...