I only have 2 mercury fillings, which I have replaced them several times since I was a kid. Even I swallowed some of the fillings along the way, drs always say it's perfectly fine (I don't know how but they say).
Today, I have been to my dr to remove the first Amalgam
fillings and put a white mercury free one. Anyway, I live in Egypt and we don't have specialized dentists to remove the mercury fillings. He drilled for few seconds and used a tool and broke the filling out.
He used a mirror to show me, and I saw a dark spot at the base of the tooth. He said it's ok, nothing to worry about it's just the base of the tooth. He put the new white filling.
Should I be worried about that dark area?