I had a bad experience, caused by me, a poor dental procedure and then not good enough follow up at the dental school clinic.
I had an old filing that my dentist at the time decide needed replacing. She replaced it, but did a poor job and left a gap between the teeth that was not there before the replacement. It was a rear tooth. I complained but to the hygienist, and was told, that will keep you flossing! The gap kept getting packed with food, I could clean it with floss, but I didn't do a good job and I ended up with decay on both teeth, After all this happened, I started going to the Dental School clinic, both teeth decayed, it was missed until it was to late and I had to get two crowns. That dentist is no longer practicing, I have to wonder if she just didn't have what it took to be a good dentist. I found a good dentist and used him for 15 years, then he got ill, sold his practice to another dentist. The new dentist seems to do good work but he raised his prices about 35% over the old dentist.
In another incident, my son was out of town at college and went to a dentist, she recommended 3 fillings, he called me, I said wait until you come home, and check with my dentist. When he come home, we got the original x'rays and my dentist looked at them examined my son and said, nothing needs to be done. I ask my dentist about it, he said, these young dentists get out of college with a lot of debt, and they take advantage of people. It made me pretty mad, because here's that dentist is in a college town, a lot of kids are having pick a new dentist while they are at school and this dentist is drilling holes in perfectly good teeth. btw, nothing has been done to "those teeth" for the last 9 years.