No, the nerve supply of the tooth cannot grow back after a root canal. The tooth is technically “dead”, with no blood vessels and nerve supply. 

Yes, a dentist can redo a root canal. The crown and the core filling materials must be removed very carefully, without damaging the already brittle tooth.

Yes, you can drive yourself after a root canal comfortably. The anaesthesia’s numbness will make sure you do not have any discomfort for at least a couple of hours after the treatment.

A tooth might look black after a root canal treatment. The dead dentine may darken because of the absence of a nutrient supply, and the tooth looks dull. You can opt for a crown, veneer, or internal whitening of the tooth to get rid of this dark shade.