Can I bleach my teeth and my underwear at the same time?

Hey, Matt:

Even though I know it is not safe to ingest bleach, I was wondering if pure bleach would harm your teeth? Trust me, I know how absurd it sounds, but it is so expensive to have your teeth whitened, and my curiosity got the best of me.

-- Tiffany K. Arthur, netland

You must be new here. Absurd? This question? Hah! It sounds like Stephen Hawking (or at least Alex Trebek) compared to some of the stuff that slithers in. That said, your question is a little like saying you know an M-80 can blow your hand off, but could you still use it to unclog a drain?

We went straight to the American Dental Association with this one and apparently struck a nerve-- like a collective root canal, I guess. They freaked. The party line: DO NOT PUT BLEACH IN YOUR MOUTH! Their science guys refused to tell us if bleach will whiten your teeth, or if it will damage tooth enamel, melt your molars, or anything else. They won't even consider the question because YOU SHOULDN'T PUT BLEACH IN YOUR MOUTH! The ADA line of reasoning: They say "Don't put bleach in your mouth," therefore you won't put bleach in your mouth, therefore they don't have to answer your question because it's hypothetical and meaningless. I'm not kidding. This is what they said. If you nose around the internet, you will find a couple of questionable people who've used bleach to whiten their teeth. One claims he put a tiny dab on a Q-tip and applied it to his teeth, and it worked. But for all we know, he might be gumming his food these days. The site hasn't been updated in six months, which I take as a bad sign.

There are plenty of risks to bathing your teeth in Clorox. Bleach is very caustic and will burn the soft tissue in your mouth. Bleach is corrosive and could harm fillings, even metal amalgam. Do you really want bleach leaking into cracks or fissures in your teeth? Inhaling bleach fumes is bad. Mixing bleach with mouth acid might turn you into a big toxic gas bag. And because teeth need ongoing treatment to keep them white, you'd have to reapply the bleach periodically. Worth the risk just to have teeth as blindingly white as your underwear and sheets? Probably not. The main component of professional tooth-whitening compounds is hydrogen peroxide, something that's quite safe to use as a mouthwash or antibacterial agent, though it won't whiten your teeth by itself.