Dentists are the worst up sellers of all. Before moving, I had all of my family checked out at the dentist we had for years. When we moved our new dentist found a lot of 'work' that needed to be done. When we asked him to consult with our old dentist to compare notes it got real awkward.
My guess is that nobody becomes a dentist because they love teeth. They do it to have a stable business. Conversely, people become vets because they love animals, and people often become doctors for the prestige or the ability to help people.
Also in my experience it’s very standard for dentists to quickly go out on their own —- many towns will have multiple dentists and none to one doctor or vet clinic.
Then again I’m seeing places like Aspen Dental popping up all over the place so who knows