It's true that correlation does not imply causation, but you're still wrong from my experience with hygienists and dentists.

They definitely and easily see a difference seen between those who floss and brush and those who just brush.

Also, those who use Sonicare, especially when used properly around the gumlines, also tend to have healthier mouths than those who brush with an old brush.

The one thing that can throw a wrench in this whole thing is smoking. Smokers' mouths are disgusting basically no matter what.

Point being, I love research, but I trust those who put their hands in tens of thousands of mouths more than skeptics on ArsTechnica article comments.

You can brush your teeth like a moron 24/7, but you still won't reach between them and remove the long-term unhealthy plaque with it - it doesn't have to do anything with a profession, but it's a physical fact. Not to mention that brushing teeth ain't proper brushing as itself, since you can easily irreversibly damage and remove the gum if using wrong technique, pressure and hard brush.

No. Gums (and possibly even tongue) are also part of your "smile". Could have said "mouth" but smile sounds better.

On the note of tongues, using a tongue scraper is a great way to get rid of nasty bacteria that causes bad breath and spreads to the rest of the teeth/gums. Cheap and effective.

> A => B does not mean !B => !A.

Uh... yes, it does. See https://en.wikipedia.org/wiki/Contraposition

Sorry to be pedantic but A => B is equivalent to !B => !A . Still, I agree that US dentists overemphasize flossing.

Not relevant given that chiropractors are making money off said claims, and dentists are not. Dentists stand to make less money when their patients take care of their oral health with something that costs literally a penny per day.