material after preparation. Crowns were ceTnented onto the teeth using zinc cement, Fuji I, Vitrerner, or C&B Metabond, The samples were thermal-cycled fer 10,OOO cycles, They were then immersed in erythrosine solution, sectioned, and observed under a microscope. Microieakage analyses were performed using a O'4 point system. The data were sLatistica!ly analyzed. There were significant differenc...

Dietary guidance to the public stresses foods or food groups as specific sources of minerals such as calcium in dairy products, iron in meats and legumes, and potassium in oranges and bananas. Dietary guidance also identifies foods that are low in some minerals (such as sodium, potassium, calcium, cooper, and iron) for patients with specific disease conditions. However, the levels of minerals a...

A method is described for obtaining the rate constant of the photodegradation process of fluorophores illuminated by a focused laser beam. The explicit kinetic equations, describing the population dynamics of excited singlet and triplet states, are averaged over the illuminated volume to describe the resulting fluorescence signal. The illumination is modulated at frequencies from 1 Hz to 100 Hz...

OBJECTIVES The purpose of this study was to determine the plaque removal effectiveness of a new powered toothbrush and compare it to that of a manual brush. METHODS This examiner-blind, randomized study used a cross-over design. Sixty-two (62) qualifying subjects were randomly assigned either to the powered brush (Arm & Hammer Spinbrush™ Truly Radiant™ Clean & Fresh Battery-Powered Toothbrush...

Room temperature phosphorescence emission of erythrosin B in sol±gel silica is studied over the oxygen pressure range from 10ÿ6 to 1000 mbar. Quenching by oxygen is signi®cant over the entire range. The Stern±Volmer (SV) intensity data can be very well ®tted using the two-site model. The temperature dependence of the phosphorescence and the delayed ̄uorescence are examined from ÿ173 to 2008C at...

BACKGROUND According to the development of resistant strains of pathogenic bacteria following treatment with antimicrobial chemotherapeutic agents, alternative approaches such as lethal photosensitization are being used. The aim of this study was to evaluate the effect of visible light and laser beam radiation in conjugation with three different photosensitizers on the survival of two main peri...

water plays a vital and essential role in our ecosystem. this natural resource is becoming scarce, making its availability a major social and economic concern. use of a large variety of synthetic dyes in textile industries has raised an hazardous environmental alert. about 17 - 20% of freshwater pollution is caused by textile effluents. these effluents are recalcitrant to biodegradation and cau...