Another root canal this week, this one a particularly unpleasent one. I spent 5 hours in the chair. 5 hours. The anesthetic wore off after 2 and half, I got renumbed but it only last another other hour. After that, it didn't really work at all. As was explained to me afterwards, when one's gums are infected, they are highly resistant to pain killers. The more inflamed the get, the more resistant they become. Needless to say, mine were pretty inflamed. So I spent the last hour and a half with little or no numbing. It took so long because the roots of the tooth were not straight like normal, but curved around in shapes which made it difficult to clean out the root completely and, you absolutely positively do NOT want to leave nerves in there.
I admit freely I screamed loudly at several points. Enough to scare the other patients and some of the staff.
That said, the dentist did a good job and despite the conditions, a very professional one. He called the next and we talked, I think he wanted to a) see how I was doing and b) make sure there were no hard feelings. There are not, I understand why he needed to do what he did and respect him for it. He did confide to me that, "it's patients with teeth like that one which cause some dentists not to do root canals at all".
I thought that was funny. My mouth is a dire warning to others.