Sloshing mouthwash for at least 30 seconds allows enough time for all your teeth to be exposed to the antibacterial properties of the rinse. “While you can do it any time, doing it before bed is best,” says Lazarof. “When you sleep, your mouth is drier, which allows bacteria to do most of the damage, so mouthwash can help blunt the effects.” (Look for a mouthwash that carries the American Dental Association Seal of Acceptance.)
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