I went to have a filling replaced a few months ago, and when he was drilling it out, he said that there was lot of decay, so he drilled it out. Then I was experiencing pain and headaches, so I went to another dentist. He said that the other dentist had drilled so deep that it was hitting my root. Did the original dentist do something wrong, or did he have to go that deep? I wasn't having pain before. If I now have that very deep filling and have a root canal, what is the future for that tooth? Is it going to be ok? I'm very nervous......please help if you can!