Not that there aren't tons of bad physicians out there who do awful things, but I feel like somehow bad dentists are a special, unique brand of awful.
For most of my life, I used my family dentist, who was an old friend of my father's and I trusted him completely. When I was in my last year of med school I needed a routine dental appointment and just picked a random dentist in the area that took my insurance.
The guy was a recent grad, and he did that annoying thing where he spent the whole time asking me questions while his fingers were in my mouth and I couldn't answer. Then he insulted me for having gone to med school and talked about how much he partied in dental school. Then he spent the rest of the time trying to convince me that if I didn't have my wisdom teeth out now, they would become infected and get a huge abscess while I was in residency. I told him my trusted family dentist said they were fine and they weren't causing me any discomfort, but he told me that they were definitely going to get infected.
On the way out, he asked me if I wanted to make an appointment for him to take them out. I said no thank you.
Sadly, I did not learn my lesson. The next year, I made an appointment with a random dentist again. He talked me into a root planing somehow. I didn't know what it was and thought it was just like a cleaning. I asked him if he'd need to numb me up and he said no, which was a blatant lie. I told him I had a dinner I was going to that evening and he said I'd be fine. I was not fine. I had to cancel all my plans for the night. I felt like I had been lied to and assaulted by him. Also, he told me I needed to have my wisdom teeth out.
From then on, I have always asked for recommendations from a friend before going to a dentist. And never had another problem (and nobody else thought my wisdom teeth were a problem). Except....
When my daughter was almost 4, I took her to a dentist for the first time. I got a recommendation for a good dental practice, but somehow there were two pediatric dentists a block away from each other and I got mixed up and took her to the wrong one. She did have a cavity and the dentist wanted to put her under sedation to fix it. I was like no way. I took her to the guy down the street and he fixed it without sedation, and she was perfectly well behaved.