Fredin B.
Studies on the Mercury Release from Dental Amalgam Fillings.
Swed J Biol Med no 3, 1988 pp 8-15.
ABSTRACT: "Several aspects of Hg release from dental amalgam tooth fillings
were examined both in vivo and in vitro. By light microscopy Hg globules
(diameter = 1-2 um) were observed on amalgam surfaces. Hg vapor was measured in
exhaled air before and after 5 minutes of gum chewing in 3 groups of subjects
with varying numbers of dental amalgams (Group 1: having symptoms similar to
chronic low dose Hg exposure, N=22; Group 2: having no apparent symptoms and
considered healthy, N=20; Group 3: controls having no amalgam fillings; N=10).
Groups 1 and 2 both demonstrated a significant 3-fold increase in Hg vapor
levels after chewing, while levels in controls remained undetectable. A mouth
rinse of hot water (55?C) in Group 2 resulted in a further increase in Hg vapor
levels. Saliva samples (1 ml) from 17 subjects in group 2, collected before and
after chewing, showed a significant 8-fold increase in Hg concentrations after
chewing. In a fourth group Hg absorption by the {*filter*}mucosa was studied, Group
4, N=10, A notably high absorption was found after 3 minutes.

****It is concluded that dental amalgam should be considered an unstable alloy
constituting a long term Hg exposure and toxicologically unsuitable as a dental
filling material." ******