I went to one dentist that said I had over 20 cavities. I didn't believe them and went to a second dentist that said I had none, but one spot was eroded and would soon become a cavity. I waited a full 10 years without doing anything and then went to a 3rd dentist, that said I have no cavities.

I'm convinced dentistry is a total scam. I'm the only person in my friends group that has never had a cavity or dental work, and I strongly suspect it's not because there's anything special about me, except that I don't go to dentists as often as most people do.