I had a re-root canal done yesterday, yep, that's right, a RE-root canal. That's where the first root canal is a failure and it has to be re-done. Apparantly the prior dentist didn't drill down far enough and the filling agent he used failed so the end result was that it was left in bad shape and was left with tissue in the tooth that blood couln't get to and thus began rotting. It then created a drainage canal through the skull bone and basically carved out a hole in the bone for puss to drain. The prior dentist wanted to fix it by amputating the roots altogether... but I went to another dentist that recommended an endontic surgeon that fixed it by re-drilling and re-filling the root canals. I can't tell you how much better I feel already, even though it's still a bit sore.