Dentists have been called lots of things. Of the good sounding are magicians and doctors. "Magicians" because someone said dentists put metal into your mouth and pull coins out of your pocket. About "doctors" I am not so sure. I think most patients call dentists Dr. So and So because of the fear of what they will have to endure in the hands of an offended dentist! And most dentists call themselves Doctor because otherwise nobody believes the "magic tricks"!
But the unholier of the adjectives is painful. On his website www.hatedentists.com, Dr. Joe Bulger, himself a renowned dentist from West Toronto, puts pain as the most common reason for this overwhelming inclination in many. For some, the inclination is instinctive and they turn their back to a dentist even at a party when they have anything sweet in their cup. Its as if a word with the dentist will pierce a cavity into their tooth and they will never know if the tooth was softened by the sweetness of their cup or of the dentist's words. Others like to keep the sentiment synonymous with certain dental procedures; and root canal treatment (RCT) seems to be their first choice.

Pain before the treatment - the anesthetic shot. This is the part of root canal treatment that is not painless for anybody. Depending on the tooth to be treated, you may need one or two pricks to numb the tooth and depending on the tooth to be treated, that prick may be painless or painful. With topical anesthetic sprays and gels and fine needles, the prick and the injection can be made almost painless in the hands of a good dentist. But if you want a "painless root canal treatment", the only catch (other than he being good at it) is to ask your dentist what local anesthetic system he uses, as the newer computerized systems maybe more comfortable for you.

Pain after the treatment - hurts to chew. After the treatment there may be some pain on chewing from that side, but it is mild enough to be taken care of by routine pain killers. However, not every story has such a quiet ending - and those which do not are precisely the ones that have bequeathed a tooth-saving treatment like root canal its notoriety. Very rarely, the infection for which the root canal is being done, flares up after the first sitting. While this cannot always be predicted and prevented, what you must know is that you are safest getting your treatment done by a specialist (endodontist) or a reputed, experienced dentist.
So is root canal treatment painful - definitely more than the regular dental checkups, making them justifiably "leisure trips"; and definitely less than the pain of "pleasure trips" - if you plan to get it done at your pleasure. Once a tooth is anesthetized, there is really no pain during or after the treatment. And the only reason no one ever said he came out smiling after a root canal is - because the lips were numb with the teeth so he couldn't feel his smile!!