Oral galvanism
Oral galvanism or amalgam disease was a term for the association of oral or systemic symptoms to either: toxic effects of amalgam fillings; or electric currents between metal in dental restorations and electrolytes in saliva or dental pulp. Any existence of galvanic pain or association of either currents or mercury to presence of symptoms has been disproven. Beyond acute allergic reaction amalgam has not been found to be associated with any adverse effects.
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