There has been significant bleaching of hard and soft corals in widely separate parts of the world from mid-1997 to the last months of 1998. Much of this bleaching coincided with a large El Niño event, immediately switching over to a strong La Niña. Some of the reports by experienced observers are of unprecedented bleaching in places as widespread as (from west to east) the Middle East, East Af...

Coral bleaching events have been increasing in frequency and severity worldwide. The most prolonged global bleaching event began in 2014 and continued into 2017 impacting more reefs than any previous occurrence. Here we present the results of coral bleaching and mortality surveys conducted in Kāne‘ohe Bay O‘ahu, Hawai‘i and compare them to the only other widespread bleaching events to impact th...

Present tooth-bleaching techniques are based upon hydrogen peroxide as the active agent. It is applied directly, or produced in a chemical reaction from sodium perborate or carbamide peroxide. More than 90% immediate success has been reported for intracoronal bleaching of non-vital teeth, and in the period of 1-8 years' observation time, from 10 to 40% of the initially successfully treated teet...

BACKGROUND Although the practice of bleaching is common worldwide, there are few studies that discuss knowledge, attitudes and practices towards bleaching. OBJECTIVE The aim of this study was to explore the knowledge, attitudes and practices towards the usage of topical bleaching agents among women. METHODS A self-administered questionnaire on the use of bleaching creams was distributed ran...

Today's society dictates that it is the norm for people to have straight, white teeth. The demand therefore for tooth whitening in dental practice has increased exponentially over the last decade. A common approach to achieving this goal is by bleaching. This article discusses clinical aspects of dental bleaching by providing an evidence-based review of current literature. Topics covered includ...

This in vitro study evaluated the surface microhardness of human enamel submitted to bleaching with 10% carbamide peroxide (CP) containing calcium or fluoride. Ninety-eight dental blocks (5 x 5 mm2) with polished enamel surfaces were randomly assigned to 7 treatment groups (n=14), as follows: without bleaching and storage in artificial saliva (control); 10% CP; 10% CP + 0.05% calcium; 10% CP + ...

This study evaluated the influence of different enamel thicknesses and bleaching agents on treatment efficacy in-depth by spectrophotometry color analysis. Eighty bovine dental fragments were previously stained in black tea solution and randomly assigned into eight groups (n=10), 1.75mm dentin thickness and different enamel thicknesses as follows: 0.5mm, 1.0mm planned, 1.0mm unplanned (aprismat...

This study describes a preclinical investigation with laser-activated bleaching agent for discolored teeth. Bleaching techniques involve a broad-spectrum approach utilizing hydrogen peroxide (3-38%) with or without heat or laser, carbamide peroxide (10-30%), or a mixture of sodium perborate and hydrogen peroxide. Extracted human maxillary central incisors were selected. In the bleaching experim...