The World Health Organization reported that the vast
majority of adults in industrialized countries have dental
caries (1) and that billions of dental fillings are placed
worldwide to restore decayed or damaged teeth (2). The
safety of these filling materials has remained largely un-
regulated partly because they were widely used prior to the
emergence of government regulations, and partly because
filling materials are most commonly considered devices by
regulatory governmental organizations and, as a result,
escape the more strict safety regulations present for pharma-
ceutical products (2). All dental amalgams contain elemental
mercury, which has led to concerns for their use (3, 4) during