I had my first cavity which occurred because they put a sealant on a molar. I had never been drilled and was scared to death. I did have my wisdom teeth removed there, though, and it went smoothly due to the nitrous oxide. I assumed that this would be available for the drilling. However, when I was in the chair and requested it, the dentist stated that they usually used this on children, not adults. She also stated that she was pregnant and could not be around the nitrous. Why did her medical condition conflict with my dental treatment? This same dentist was also very condescending a year or so before. I had heard that mercury fillings could be replaced with a see-through filling. When I asked about it, she laughed, looked at the dental hygienist, and said there was no way this could be done. I will never go back there again.