Brushing (and flossing) is the best way to protect your teeth and gums -- but not if your toothbrush is in bad shape. "Toothbrush bristles that are worn or frayed from use cannot effectively remove plaque, which is critical to maintaining healthy teeth and gums," says Sebastiana Springmann, a dentist in Williamsburg, Va.
* Don't cover up brushes between uses. Allow them to air-dry instead. Bacteria and other organisms will grow faster on bristles kept in a closed, damp environment.
* Rinse them thoroughly. After each use, hold brush under running tap water until you've cleaned off all remaining toothpaste and visible debris.
* Store them correctly. Place brushes in an upright position to best air them out. Also keep them at least 6 feet away from a toilet to avoid contamination with (yuck) airborne particles after a flush.
* Don't share brushes. You'll be swapping germs with the other user, which can make you sick. If you store more than one brush in the same container, keep their heads completely separated.
* Replace them often. Get a new brush at least once every three or four months, and after each time you've been sick, according to the American Dental Association. If bristles look worn or frayed, the brush needs to go. Children may need replacements more often than adults.
* Consider disinfecting them. Some dentists recommend soaking brushes in an antibacterial mouthwash such as Listerine for five minutes a day. You also can buy an ADA-approved sanitizer machine, which uses ultraviolet lamps or steam and dry heat to fry nearly all bacteria and viruses. Just note: Studies to date haven't confirmed a health benefit, and not all dentists believe frequent disinfecting is necessary.