OBJECTIVE To investigate the influence of different bleaching techniques on subsurface physical properties of composite and polyacid modified composite tested via determination of micro-hardness. METHODS Specimens of Tetric Flow, Tetric EvoCeram and Compoglass were light cured (2.5mm thickness) and stored in artificial saliva for 2 weeks (n=12/group). The samples were only removed for applica...

Coralline algae are important components of coral reefs and are involved in reef building via calcification, cementation, the synthesis of anti-fouling compounds and the synthesis of allochemicals to aid recruitment, settling and metamorphosis of reefs species. Using Corallina officinalis we have shown that these algae undergo temperature-related bleaching at similar temperatures to those known...

The aim of this in vitro study was to evaluate enamel microhardness following bleaching treatments using either high- or low-concentration hydrogen peroxide (HP) agents containing calcium and/or fluoride. Sixty enamel blocks were bleached with 1 of 6 different bleaching agents (n = 10). The high-concentration HP agents were Whiteness HP Maxx (35% HP), Whiteness HP Blue (35% HP, 2% calcium gluco...

It is well known that clinical bleaching can be achieved with a solution of 30% hydrogen peroxide (H2O2) or H2O2/titanium dioxide (TiO2) combination. This study examined the hypothesis that TiO2 coated with hydroxyapatite (HAp-TiO2) can generate reactive oxygen species (ROS). ROS are generated via photocatalysis using electron spin resonance (ESR). The bleaching properties of HAp-TiO2 in the pr...

Tooth bleaching is a widespread dental treatment with important psychosocial antecedents and outcomes involved. In the activation of in-office bleaching agents, a selective light radiation, that is, a diode laser seems to be a positive choice to decrease the time of bleaching without surface modification and with no residual tooth sensitivity for maximum effect and minimal clinical and psycholo...

In this study we investigated the variation in grazing scar densities between bleached and non-bleached colonies of massive Porites species in Sekisei Lagoon (Okinawa, southwestern Japan) during a mass bleaching event in 2016. The grazing scar densities and bleaching susceptibility varied among neighboring colonies of massive Porites spp. However, non-bleached colonies had significantly more su...

Methods: Twenty-four bovine teeth surfaces were submitted to three bleaching techniques with two commercially available 35% hydrogen peroxide bleaching agents (n=8). The specimens were immersed in red wine for 48 h at 37°C and submitted to the bleaching techniques. Color changes were measured before and after staining as well as immediately after and 24 h after the bleaching treatments, with tw...

OBJECTIVE To study the effect of atmospheric pressure plasma (APP) jet as a potential accelerator of the degradation of hydrogen peroxide in bleaching gels which could lead to better and faster bleaching. MATERIAL AND METHODS 25 pastilles of hydroxylapatite were colored in green tea for 8 hours and were randomly divided into five groups (n = 5). The bleaching process was performed with 30% an...

2014 marked the sixth and most widespread mass bleaching event reported in the Northwestern Hawaiian Islands, home to the Papahānaumokuākea Marine National Monument (PMNM), the world's second largest marine reserve. This event was associated with an unusual basin-scale warming in the North Pacific Ocean, with an unprecedented peak intensity of around 20°C-weeks of cumulative heat stress at Lisi...

BACKGROUND Climate-induced coral bleaching poses a major threat to coral reef ecosystems, mostly because of the sensitivities of key habitat-forming corals to increasing temperature. However, susceptibility to bleaching varies greatly among coral genera and there are likely to be major changes in the relative abundance of different corals, even if the wholesale loss of corals does not occur for...