I just had a conversation with a friend who's a dentist, that I need to share.
She was complaining about how in the (corporate) dental office she's in, there's a new dentist who's billing insane amounts of money (up to $3,000 in dental bills an hour, paid by insurance). This new dentist recommends and installs crowns when a regular filling would have worked, and "finds" multiple cavities where there are actually zero cavities. It's mostly unnecessary work that destroys people teeth, and there's no limits on this kind of unethical behavior. Apparently there's zero checking by the insurance companies. The corporate managers love it, because the revenue per hour is huge.
Anyway, I've experienced and heard of situations at dentist's offices that seemed fraudulent and sketchy. But this is first-hand evidence from another dentist.
I'd never trust a dentist. I think that whole "go to the dentist twice a year" thing is just to give them an opportunity to extort you. I haven't been to a dentist in about 4 years.