I know exactly what you mean and I also got tired of the glazed look and stopped trying to explain, but I now try to mention it casually (I think it might help to say" mercury poisoning from my dental fillings" as opposed to just saying mercury poisoning) and go on as if I didn't say anything unheard of. Their reactions are the same and they don't understand the magnitude of your problems, but I feel that every time someone mentions this to others that it helps to make it seem less "unheard" of and like anything else the more you hear of something the more it seems that maybe there is something to this after all.

I want to do all that I can to uncover the cover-up that the dentists are participating in.