I second you on the silver fillings. The mercury fillings now a days are rarely done due to their ill effects on body in long run, however due its property of strength, it is stilll done in many parts of the world and ofcourse being cheap than white fillings. I would say if you have a silver filling done on your teeth, go to your dentist to see if your insurance covers white fillings. The mercury starts to dissolve into the oral fluids and tend to do so for years causing accumulation of mercury in the body, and if the threshold is crossed the toxicity occurs.
Amalgam also needs much tooth preparation which renders tooth to fracture if the integrity of tooth margin collapses.
Amalgam is also very poor in Aesthetics, which nowadays is a primary factor of patients.
Amalgam had its virtues of strength but its effects on body surpasses the former, so whenever you go to see a dentist, discuss thoroughly about silver fillings and whether you can have white fillings instead.
Also if one has done amalgam fillings some years back in more than 3 or 4 teeth, consider removing them for white fillings. However, 1 or 2 teeth can be seen as borderline cases.

P.S. i will be making a thorough post about amalgam fillings, health hazards and its replacements in coming days.

Kind Regards
Dr Himayun