The use of mercury amalgam is still an established dental practice in many countries,35 although questions have been raised about children’s exposure to mercury from amalgam fillings. Mercury forms an amalgam when combined with other metals, such as gold, silver, and copper. There is an association between the number of dental amalgam fillings and mercury concentrations in urine and blood.122,123 Recent longitudinal studies on the use of amalgam fillings in children did not observe any negative effects on neuropsychological function within a 5-year follow-up period.124,125 The use of amalgam fillings for children has been discontinued in several countries due to the precautionary principle. For example, since 1997 the use of amalgam fillings for children is no longer permitted in Germany.126 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3096006/