Alex, rinse your mouth with warm salt water a few times a day. A tooth with a root canal is bothering you? How long ago was it worked on? Sometimes if takes a while for the tooth to settle down after a root canal. Sometimes if a root canal is done improperly it needs to be done over, or the tooth pulled. If it is not getting worse, then have patience, and keep rinsing a few times a day with salt water. It might settle down after a while.

There could be plenty of mercury within the gums or other structures near the teerg. My gums were guite irritated for a long while after my amalgams were replaced.