[davoneus]

Intuitively, I suspect any acid is bad for your teeth. But I see that statement primarily from Dentists, and their track record in a number of areas is less than stellar. Prime example: Flossing and 6 month checkups. Neither of which have good scientific evidence, despite their widespread promotion.

[cableshaft]

I go every three months, and they have a good amount of tartar to clean off my teeth then. Also before I did that I was having pretty significant pockets for gum disease for all my teeth (it was close to the point where it's irreversible).

It's mostly under control now, except for problem areas in two specific spots, but even those are still better than they were.

I haven't really changed my dental hygeine habits other than going in for routine cleanings twice as often, so it's definitely helping.

[eru]

From anecdotal evidence: when I stop flossing for a few days, my gums start bleeding.

Not sure what suspicious extra super powers your dentist suggests flossing has?

[musicale]

6 month checkups (especially with expensive x-ray imaging) are scientifically proven to improve dentist income.