It has long been known that red wine causes teeth to stain. But white wine?
A recent study by NYU dental researchers found that drinking white wine can also increase the potential for teeth to take on dark stains.
The researchers compared two sets of six cow teeth, whose surface closely resembles that of human teeth, and used a spectrophotometer, an instrument that measures colour intensities, to evaluate staining levels.
They found that teeth soaked for one hour in white wine before being immersed in black tea had significantly darker stains than teeth immersed for one hour in water before exposure to the tea.
Acids in wine penetrate tooth
"Dipping teeth in white wine for one hour is similar to the effect of sipping the wine with dinner," said Dr Mark Wolff, Professor and Chairman of the Department of Cardiology and Comprehensive Care at New York University College of Dentistry, who oversaw the study, which was led by Ms Cristina M. Dobrescu, a third-year student at New York University College of Dentistry.
"The acids in wine create rough spots and grooves that enable chemicals in other beverages that cause staining, such as coffee and tea, to penetrate deeper into the tooth," Wolff explained.
Still, red wine continues to beat white wine when it comes to staining teeth. When the researchers repeated the experiment with red wine, the resulting stains were significantly darker than those in the white wine group.
"Red wine, unlike white, contains a highly-pigmented substance known as chromogen," explained Wolff.
But he added that connoisseurs concerned about staining need not cut back on their consumption. "The best way to prevent staining caused by wine, as well as other beverages, is to use a toothpaste containing a whitening agent," advised Wolff. – (EurekAlert, April 2009)
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