My tooth no. 45's been decayed for many years without any treatment. what remains now is the root which sometime aches. what's the best treatment now?

See a dentist: There are a few various options which could resolve the situation you have described (root canal, extraction, implant,etc.) I can appreciate your concern about your dental health, but finding a proper diagnosis and treatment may be the best answer to your problem. Rec.: see a dentist for examination, x-rays and treatment. Take good care.

Dental exam: The best thing to do,is start at the beginning and have a dental exam. This will determine your options and answer your questions about treating this tooth. If there is just a little bit of root left it may not be treatable and you would want to remove and replace this tooth.

Check tooth: Need to go to a dentist to evaluate and see if the remaining tooth structure is still restorable or hopeless . Different options available to replace the tooth if had to be pulled

Hard to say...: But for most things, if they're left to rot for a few years, they need to be discarded. The best thing you can do for your self its to find a terrific local dentist. have yourself examined and follow up on necessary care.

Extraction.: Infected root must be removed or infection will spread. Damaged tooth and supporting bone requires management (replacement) by your Dentist. Please go soon.

Extraction/replace: Extraction of the root and replacement with a dental implant and crown. See the prosthodontist for evaluation and referral to surgeon so they can treat you as a team. Good Luck.