Physical and mental health related to dental amalgam fillings in Swedish twins.

In the past years increasing attention has been paid to possible adverse health effects of mercury exposure from dental amalgam fillings. To evaluate possible health effects from amalgam fillings, dental status registered by specially trained nurses was obtained from 587 subjects included in the ongoing Swedish Adoption/Twin Study of Aging (SATSA). Data on physical and mental health were collected and memory function tested. Mean age was 66 years (SD 9, range 46-89). In the entire material, 25% of the individuals had no own teeth and in the group with own teeth the median number of teeth surfaces filled with dental amalgam was 15 (range 0-65). Analyses of associations between number of surfaces filled with dental amalgam and a number of scales estimating somatic and mental health and memory functions were performed both for the entire group and for individuals having at least 12 teeth. Regardless of the sample, no negative effects on physical or mental health were found from amount of dental amalgam, even after controlling for age, gender, education and number of remaining teeth. When using a co-twin control design with twin pairs discordant for amalgam exposure, no negative health effects associated with dental amalgam were detected. This study does not indicate any negative effects from dental amalgam on physical or mental health or memory functions in the general population over 50 years of age.