Hi!
Just posting an update to this - I have had all of my mercury fillings removed for a year now (after spending time in Romania - the land of cheap dentistry), but have not noticed any difference in my skin or overall health.
I do have some white crowns under which is some type of metal, which may contain mercury but probably contains nickel, which apparently may have a negative effect on the immune system (yay!). At the moment however I don't feel like getting those removed too!
Best wishes
Mark