I’ve had two in the past, had my third just three days ago, my gums are still a little raw. My most recent root canal was on a hyper-sensitive tooth, so there was initially some pain, but once the dentist applied another couple of doses of anesthetic, it was painless, basically a more prolonged filling. The only thing I’d add is that my dentist recommended ibuprofen for after the anesthetic wears off, since there may be some pain, I’d second that recommendation since your gums will be sore for a few days