Need help with root canal..please help.?

i had the root canal done around 11 years ago. i am 28 now and went to dentist he did the full mouth xrays and he said i need to replace the crown because its too old which i can understand. he also said that whoever did the root canal did not do it all the way up he said it looks like that it was partially done (its my tooth # 3 on top right) i have no pain no symptoms at all but the only thing i am concern about is to have the crown replaced. do i realy need a new root canal while the dentist replace the crown? my another question is... what is the life of the root canal? if i dont have the new root canal done and leave the (partially done) there would it cost any problems in long run? or should i have the new complete root canal done while getting the crown replaced? and does it pain during or after the root canal procedure? please help. thanks,

Need help with root canal..please help.?
If done properly, a root canal can last a lifetime. However, in the case of yours, it sounds like the dentist who did it didn't do it properly and it will have to be redone. That's because there's dead material in there that could become re-infected. I've had root canals that were rather painless because the tooth was dead and the root shaft was empty. In some cases, the dentist can drill into the tooth and some air will actually escape. In the case of one of mine, the dentist opened the tooth and was able to see all the way to the end of the shaft (it was a front tooth).
Reply:That's a lot of questions that should be asked of your dentist. He can explain until you are feeling more secure about having this done. I had root canal done and dentist said once done never have to have it done again in same tooth. Good Luck!
Reply:Most dental work when done properly can last a long time. But when things fail it's not always the dentist's fault. People use their teeth...A LOT. Chewing ice, biting nails, etc, can all have adverse effects on your restorations. In your case, it sounds like the job might not have been done right, but if you have any concerns about the dentist "ripping you off" or taking advantage of your insurance, get a second opinion. I doubt this is the case but if anything sounds fishy don't hesitate. You could also go to a dental school to have students and their professors check you out where there's no profit involved.