Toothbrushes: When to Replace Them, Where to Keep Them


As you reach for your toothbrush each morning, you may not realize what’s hanging out on its bristles.

“Toothbrushes can become contaminated with oral microbial organisms whenever they are placed in the mouth,” says Sharon L. Cooper, PhD. 

Viruses and bacteria from an infected person’s mouth can live for weeks on a toothbrush surface, and continue to cause illness, says Cooper, clinical associate professor of periodontology at the University of Florida College of Dentistry.

Even normal, healthy microorganisms can cause infections, especially if they enter your gum tissue due to an injury, a break, or an oral ulcer, she adds. 

Toothbrushes don’t have to be sold in sterile packaging, so they may have bacteria right out of the box says the American Dental Association’s official statement on toothbrush care. 


Keep It Clean

You may not give much thought to cleaning your toothbrush, since you’re wetting it every day to scrub your teeth. However, it’s important -- and easy -- to do.

Wash it. Give your toothbrush a thorough rinse with tap water to remove debris. If you have a systemic illness or immune disorder, you may want to soak it in antibacterial mouthwash or run it through the dishwasher, Cooper notes. 

Try deep cleaning. There are many types of toothbrush sanitizers on the market, says Cooper. Some even use ultraviolet light to kill microorganisms.

Store it properly. After use, don’t pop that wet toothbrush back into your medicine cabinet, drawer, or bathroom cup and forget about it.

Store it upright, in a rack or cup, but not somewhere it can’t dry out. Look for a cover that lets air and prevents mold, but isn’t completely sealed. The lack of air can foster bacteria. 

When to Call It Quits

How long should you keep a toothbrush to prevent the ick from building up? Here are a few useful tips:

Know when to let go. Replace your toothbrush about every three to four months, or when it shows signs of wear. “Frayed bristles will not clean the teeth and gums adequately,” says Cooper.

Toss toothbrushes after illness. Throw away a brush you or anyone in your home used while they were sick. 

Yes, that means all toothbrushes. Treat electric or power models the same way you handle an old-fashioned one. Chuck the brush attachment after an illness or when the bristles begin to show signs of wear, Cooper says. 


No Sharing

Tempted to lend a toothbrush to a family member? Don’t.

Toothbrush sharing can transfer saliva and bacteria – even the kind that causes tooth decay. “Tooth decay is considered an infectious disease … one more reason not to share or borrow a toothbrush," Cooper says.