My dentist screwed up a tooth filling and now my tooth is rotten from the inside, down to the jaw. And she tells me that the only way to fix this is by getting two root canals (since it is a molar). Isn't that lovely? =]
But I don't have the money for root canals... if I did, I'd use it to sue her first.
A similar thing happened to me, I told my dentist that my tooth hurt like hell, but every dentist I went to (I went to like, eight) told me that it was just another tooth coming up really late and I was a wuss for being so whiny about teething. I insisted it was the tooth that hurt and my gums weren't sore.
Three months later, the pain is back and it turns out that tooth had rotted so badly from being untreated that I needed a root canal. Though money wasn't a problems since, free healthcare, woop woop.