How much do you know about oral hygiene? Odds are, not much. After 1,500 people took the American Dental Association's first oral health quiz, their overall grade was a dismal 'D.'

The ADA says that although we should only brush our teeth twice a day, nine out of 10 adults thought brushing after every meal is necessary. They also thought flossing twice a week was sufficient, while the ADA recommends doing it daily.

In addition, two-thirds thought replacing their toothbrush twice a year was fine, but the ADA says we should do that every three or four months. And fully three-quarters of people didn't know when a child should first visit a dentist (the official recommendation is six months after the first baby tooth appears or no later than the child's first birthday).

Thanks to all those sugarless gum ads, 81 percent of respondents mistakenly thought sugar causes cavities, when it's really germs in the mouth that feed on sugar that do the trick. And did you know cavity-causing germs can be passed from person to person? More than half of those who took the quiz didn't.

"The results of the survey were quite shocking and really show how important it is for people to become more involved in their own oral health," said William R. Calnon, D.D.S., ADA president and a practicing dentist in Rochester, NY.

Want to learn more? Visit the ADA's new website,

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