Recent outbreaks of coral bleaching and disease have contributed to substantial declines in the abundance of reef-building coral. Significant attention has been paid to both phenomena in order to determine their effect on reef trajectories. Although each is positively correlated with high temperatures, few studies have explored the potential links between bleaching and disease. A longitudinal s...

In this research, the application of walnut shell ash, as an adsorbent for soybean oil bleaching, has been investigated. Therefore, neutralized soybean oil was bleached with 1 and 2% of walnut shell ash as well as commercial bleaching earth. Then, a series of chemical tests such as amounts of carotenoids, chlorophylls, peroxide value, and free fatty acid content of bleached oils and oil retenti...

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BACKGROUND To determine the susceptibility of teeth for repigmentation after bleaching. MATERIALS AND METHODS Forty premolars were assigned to three groups (n = 12). Group 1 was bleached using 30% w/v hydrogen peroxide 15 min 3 times a day every other day for 4 days. In Group 2 was bleached using 16% carbamide peroxide (Polanight), 90 min a day for 15 days. 2 days later, the shades of the ble...

INTRODUCTION Tooth bleaching is based on hydrogen peroxide application. The Objective of this study was to determine whether dental bleaching agents affect metalloproteinases-mediated dentin collagen degradation. METHODS Human dentin specimens were subjected to different treatments: (1) untreated dentin; (2) demineralization by 37% phosphoric acid (PA); (3) demineralization by 37% PA, followe...

Aim: This randomizes clinical trial evaluated of color change, rebound effect and tooth sensitivity associated with power and at-home bleaching techniques. Methods and Materials: Anterior teeth of twenty volunteers were randomized into two balanced groups (n=20) ; Power and at-home bleaching. Color was recorded before bleaching ,immediately after bleaching, at two weeks, one, three and six mont...

Coral reefs are one of the world's most threatened ecosystems, with global and local stressors contributing to their decline. Excessive sea-surface temperatures (SSTs) can cause coral bleaching, resulting in coral death and decreases in coral cover. A SST threshold of 1 °C over the climatological maximum is widely used to predict coral bleaching. In this study, we refined thermal indices predic...

The aim of this study was to determine attitudes of final-year dental students in Cardiff, Cork and Malmö towards tooth whitening. Following receipt of ethical approval, pre-piloted questionnaires were distributed to final-year dental students in Cork, Cardiff, and Malmö as close as possible to graduation. The questionnaire sought information relating to various opinions and attitudes towards t...

OBJECTIVE Numerous studies investigated the impact of bleaching procedures on enamel microhardness. The outcomes of these studies reveal inconsistencies regarding the fact whether a microhardness reduction due to bleaching occurs or not. Aim of the present review was to summarize the existing literature of external bleaching therapies, which used microhardness tests for evaluation of possible e...

AIM This study evaluated the effect of adding calcium or fluoride to 35% hydrogen peroxide (HP) bleaching gel and the effect of human saliva on the microhardness of sound and demineralized enamel, using an in situ model. MATERIALS AND METHODS Cylindrical bovine enamel specimens (3 × 2 mm) were divided into two groups (n = 30): sound enamel (SE) and demineralized enamel (DE). Each group was di...