Mercury reactions in the human mouth with dental amalgams

This is a preliminary study of the reactions of mercury (Hg) in the human mouth with dental amalgams. It was conducted by analysing saliva samples from subjects with amalgam fillings and control subjects with no amalgams. Samples were collected both prior to and after cleaning the mouth. These samples were analyzed for elemental mercury (Hg⁰), inorganic mercury (Hg²⁺) and methylmercury (MeHg). We concluded that the concentrations after cleaning represented the systemic concentrations. Hg²⁺ and MeHg were found in all systemic samples from both subjects and controls, while Hg⁰ was found only in the samples from subjects with amalgams. In the control group, the concentrations found before and after cleaning the mouth were equivalent. In the amalgam group, concentrations of Hg²⁺ found before cleaning the mouth were 10 to 40 times higher than those found after cleaning, suggesting that the oxidation reaction of Hg° into Hg²⁺ takes place. For MeHg, a similar but less pronounced pattern as Hg²⁺ was found, supporting methylation in the mouth.