The town I grew up in had a very high flouride content in the water. Flouride is a tricky thing - you need a certain amount of it for healthy teeth. But since I had too much of it as my teeth were forming, it destroyed the enamel on my teeth. Now if I so much as look at something sweet, I get a cavity. it's been that way pretty much my whole life. So every visit to the dentist is miserable for me. Once as a child, I had 7 teeth pulled in one afternoon. I've got fillings in every tooth (thankfully the front ones are the kind that blend in with the teeth).
Dentists and I are not friends.