Old mercury filling material in your teeth is negatively affecting you. If you leave it in place the question is whether or not chelation will worsen the affection. I do not know the answer but at the least, chelation will likely change your condition.
According to Huggins, a single mercury filling that was in place 20 years before being totally/properly removed IE. not there anymore, continues by way of residual outgassing, to negatively affect the person long after they had it removed .... the gift that keeps on giving :(