I recently moved from a private dentist to a NHS-funded one in the UK. They're quite hard to get into usually, but I tormented the reception staff with weekly calls until "a spot opened up".

I had a series of work done at my previous, private, dentist. He told me a had a bunch of issues with my teeth, that might include a root canal at some point in the new future, and work needed as my wisdom teeth start to come through.

I had my first check-up with the new dentist; "Your teeth are in very good condition, I have no idea why they suggested you might need a root canal". Every follow-up has been with a different dentist, and none of them have recommended treatment of any kind. It's utterly bizarre. I've never gone this long without a need for treatment of some kind. I wasn't aware of how much profiteering goes on until moving to something that is a public-service rather than a for-profit practice.