BACKGROUND Bleaching the discoloured teeth may affect the tooth/composite interface. The aim of this in vitro experimental study was to evaluate the effect of vital tooth bleaching on microleakage of existent class V composite resin restorations bonded with three dental bonding agents. METHODS Class V cavities were prepared on buccal surfaces of 72 intact, extracted human anterior teeth with ...

The National Monitoring System for Coral Reefs of Colombia (SIMAC) monitors the impact of some of the most important agents of coral tissue loss (bleaching and/or disease) in the Colombian Pacific coral formations since 1998. Physiological bleaching is among the main results of stress in the area. Signs of coral diseases resembling bacterial bleaching such as White Plague and White Band, were o...

the aim of this work was to study the ability of two biodegradable chelating agents, nitrilotriaceticacid (nta) and ethylenediiminopropanedioic acid (eddm) to complex metals, in the treatment of the pulp,prior to a totally chlorine free (tcf) bleaching process, and compare with the ethylenediaminetetraacetic acid(edta) performance. firstly, speciation efficiency index (sei) was calculated by co...

Occupational allergic contact eczema and asthma caused by bleaching agents is seen in hairdressers. Bleaching agents contain persulfate salts, which are known to induce immediate reactions such as rhinitis, asthma, contact urticaria, and anaphylaxis. The immunologic mechanism is not, however, fully understood. The specific inhalation challenge test is considered to be the gold standard for diag...

Comparative study on organosolv pulping method have been done by using various mixtures of water and organic solvents as delignifying agents including ethylene glycol-water mixtures, ethanol-water mixtures and acetic acid-water mixtures to extract cellulose from agricultural crop biomass (Oil palm empty-fruit bunches-OPFB). The yield of organosolv pulping with ethylene glycol-water mixture, eth...

AIM To evaluate the bleaching efficacy of 35% carbamide peroxide, 35% hydrogen peroxide and sodium perborate for intracoronal bleaching of root filled discoloured teeth. METHODOLOGY Extracted premolars were artificially stained using whole blood then root canal treatment was performed. After obturation, a 2 mm intermediate base was placed 1 mm below the buccal amelo-cemental junction. Intraco...

Objectives. Extra radicular diffusion of hydrogen peroxide associated with intracoronal teeth bleaching was evaluated. Methods. 108 intact single rooted extracted mandibular first premolars teeth were selected. The teeth were instrumented with WaveOne system and obturated with gutta percha and divided into four groups (n = 27) according to the bleaching materials used. Each main group was divid...

ince bleaching has become a popular procedure, the effect of peroxides on dental hard tissues is of great interest in research. Purpose: The aim of this in vitro study was to perform a qualitative analysis of the human enamel after the application of in-office bleaching agents, using Scanning Electron Microscopy (SEM). Materials and Methods: Twenty intact human third molars extracted for orthod...