The quicksilver quest : two psychological studies investigating the effects of mercury in dentistry : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Wellington Campus, New Zealand

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The longstanding debate over the safety of mercury in dentistry has latterly moved from scientific argument to public health dilemma. Mercury is a neurotoxin. Adverse psychological outcomes can result from exposure, so The Quicksilver Quest aimed to investigate mercury in dentistry from a qualitative, critical health psychology perspective, and a quantitative, neuropsychology assessment. The qualitative study used focus group methodology to explore micro-mercurialism linked to dental amalgam fillings. A random sample of people, who had been medically diagnosed with mercury poisoning, formed seven focus groups. The discussion of experiences, beliefs, and health was analysed for themes and issues. The main findings were that the participants were not a homogeneous group, as had been anticipated, but fell into categories differentiated by their symptoms, fiscal resources, and motivation. A placebo effect was rejected as an exclusive explanation for the positive health outcomes reported by those who had had amalgam removal and detoxification. The quantitative study investigated the long-term effects of occupational mercury exposure on a cohort of women in dentistry. The aim was to test the null hypothesis: that women who endured high occupational mercury exposure in the 1970s (43 participants), and matched controls (32 participants), would show no between-group differences on a general and reproductive health survey, and a nine-test neurobehavioural assessment. Results generally supported accepting the null hypothesis. Significant exceptions were current symptom experience, reproductive health, and two mood subscales. There was a suggestion of peripheral nerve damage in the exposed group. Overall, the general discussion systematically reviews tension points in the debate, in light of a proposed model of tolerance to mercury. This begins to explain how it might appear that mercury in dentistry is safe for dental personnel, as pro-amalgam debaters claim, yet unsafe for some dental patients, as anti-amalgam debaters claim. Further study is suggested for occupationally exposed women, on tremor, and to test the proposed tolerance to mercury model. Finally, as the debate has a political aspect, a recommendation is made for a shift in public health policy to dental amalgam being restricted to use only in an adult population.
Content removed due to copyright restriction: Jones, L. M. (2004). Focus on fillings: A qualitative health study of people medically diagnosed with mercury poisoning, linked to dental amalgam. Acta Neuropsychiatrica, 16(3), 142-148. Jones, L. (1999). Dental amalgam and health experience: Exploring health outcomes and issues for people medically diagnosed with mercury poisoning. The Bulletin, 97, 29-33.
Dental assistants, Health and hygiene, Dentists, Clinical health psychology, Neuropsychology, Mercury toxicology, Dental amalgams, Fillings (Dentistry), New Zealand, Dentistry