Are you talking about anaesthesia in the sense of general anaesthesia (loss of consciousness and all that)? Because that's really not needed for a root canal.

Are you talking about anaesthesia in the sense of general anaesthesia (loss of consciousness and all that)? Because that's really not needed for a root canal. I've had many and generally the dentist will make an injection to numb the nerve, have you wait 15 minutes, and start working. In case of discomfort they'll give an extra injection.