l received a deep filling on a tooth about a year ago.After that it has always been sensitive to cold, but did not seem like a problem.Now it is slightly loose and has an abscess in the gum near it.Will l just need a root canal or will my tooth not be able to be saved? It is pretty painful andl have not been able to chew on that side recently.

Sounds like u will need Root Canal Treatment (RCT) & then it can be saved by the build up (filling) & a crown (cap).

You can read the following if u have any question about the RCT :

http://..com/question/index;_ylt=AtnoXiGb6kaN2fMZZ236Edrty6IX;_ylv=3?qid=20080905203432AA3GHx4&show=7#profile-info-MUsAkZdhaa

[Sorry for the typo : it should be ''tooth'' & NOT ''otth'']

Hope this helps :)

Good luck !!

EDIT : The clue is that the tooth is ''slightly loose & has an abscess in the gum near it.''

That means the bone loss around it due to infection is not severe enough to require extraction. You definitely need RCT because of the abscess / infection.

sorry you can not do anything, see the dentist.

l really wish l could answer ur question. Without an x-ray & seeing the tooth it is difficult to diagnose.
Since the tooth already has a deep filling & has been sensitive all this time, prognosis is slim.
The tooth is now mobile & there is a noticeable infection. The infection has, possibly, been there for a while, & has ''eaten'' away at the bone, which anchors ur tooth into ur jaw. That is why the tooth is now loose.
Your dentist should have told u that the filling was deep & it may require a root canal. The dentist also should have told u to call right away if the tooth was sensitive to hot & cold ( that lasted more than a few seconds ).
Call ur dentist & schedule an appointment. l hope that root canal therapy will be sufficient.
If it isn't, there r plenty of other options once the tooth is extracted. The best is an implant. Othere options include a bridge or a flipper.