Cranberry juice holds important clues for preventing cavities, say researchers from the University of Rochester Medical Center. A team led by oral biologist Hyun (Michel) Koo, DDS, PhD, has discovered that the same traits that make cranberry juice a powerful weapon against bladder infections also hold promise for protecting teeth against cavities. Koo found that cranberry juice makes it difficult for the bacteria that cause cavities to cling to tooth surfaces.

“Scientists believe that one of the main ways that cranberries prevent urinary tract infections is by inhibiting the adherence of pathogens on the surface of the bladder. Perhaps the same is true in the mouth, where bacteria use adhesion molecules to hold onto teeth,” Koo said.

Koo’s team also found evidence that cranberry juice disrupts the formation of the building block of plaque, known as a glucan. Like a mason using cement to build a wall brick by brick, bacteria use enzymes known as glucosyltransferases to build dental plaque piece by piece, quickly forming a gunky fortress that covers the tooth and gives bacteria a safe haven to munch on sugar, thrive and churn out acid. Koo’s team found that cranberry juice prevents bacteria from forming plaque by inhibiting those enzymes and by stopping additional bacteria from glomming on to the ever-growing goo.

But don’t even think about running to the juice aisle in the grocery store to prevent tooth decay, Koo said. Unless it’s pure cranberry juice, the sugar that is usually added can cause cavities, and the natural acidity of the substance may contribute directly to tooth decay.

Koo hopes to isolate the compounds within the juice that pack an anti-cavity punch. The substances could then be added to toothpaste or mouth rinse directly.

University of Rochester Medical Center, Nov 23, 2005