Ten years ago I was wondering the same thing. I did a lot of research on the net and talked with my dentist (who was the first person to notice my health decline).
I decided that – for me- the stress (and expense) of having my fillings removed and replaced with the alternate fillings was not worth it. Also, back then, the alternate fillings were not as strong and needed to be replaced more often than regular silver fillings.
My bloodwork did not reveal heavy metal poisoning. Ten years ago there was a test to check levels of mercury in your mouth. At the time is sounded like a con, but perhaps it is now considered an accurate medical test.
Mercury poisoning is a real and dreadful condition. However, I think dentists would have been the first to be affected if it was caused by the amalgam.
I continue to blame my CIDP on an infection.