If you must have a root canal, I urge you to investigate the use of biocalix as filling material, rather than gutta percha. Recent research indicates that biocalix discourages the growth of anaerobic bacteria in the canals. O nce the amalgams are replaced, mercury is still bound very tightly to tissues in the body. The half-life of mercury in nerve tissue is seventeen years. Chelation is a procedure whereby you ingest chemicals that bind to mercury and help in it's excretion.
Many methods are controversial, and some are harmful.
Chorella is a green powder that is a one celled alga. It bonds to heavy metal very well. I would use it cautiously and sparingly until your amalgams have been removed for a period of six months. Then I would take it daily and liberally unless you are sensitive to it. Buy it in bulk and add it to your vegetable juice.