Category Archives: Preventive dentistry

You don’t need to change your toothbrush after being sick

I was in a Walmart yesterday after work, and ran into this display:

Change your toothbrush after a cold or flu

Give me a break, Colgate! I’m disappointed in you for this marketing gimmick. There is absolutely no need to change your toothbrush after a cold. The idea that invisible nasties are lurking in your toothbrush sounds gross, but have you ever heard of anyone re-infecting themselves after a cold or flu? No. Neither have I. Basic biology teaches us that we fight off disease by creating antibodies to the disease. Once you’ve built up the antibodies and cleared the disease from your system, you’re not going to be able to re-infect yourself. And research shows that there is no need for a new toothbrush after being sick.

Even if it were possible to catch the same virus twice, you have an excellent household method for sterilizing any toothbrush – simply dip it in Clorox or any similar household bleach for about a minute. That will kill everything.

Bleach is so good at sterilizing, you could take your friend’s toothbrush, and even if he has tuberculosis, pneumonia, or hepatitis, a one-minute soak in bleach straight from the bottle will kill all the nasties. We would have used Clorox to sterilize our dental instruments, but it is extremely corrosive to metals. For plastics, however, it works great.

Change your toothbrush when it wears out. When the bristles start to splay out, change it. If the bristles look good, keep using it. It’s as simple as that.

When to replace a toothbrush
There is no need to replace a toothbrush until it is worn out. The bottom toothbrush should have been replaced long ago. The top toothbrush is fine, no matter how long it has been used.

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