One of the European Commission's (EC) top scientific bodies, the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR), is calling for public comment on a new report in which it largely downplays concerns about exposure to mercury in dental amalgam while saying that further study is needed.

Background

SCENIHR has long been interested in the issue of dental amalgam, a mercury-based filler that is used to treat dental problems like cavities and regulated as a medical device. In 2008, SCENIHR issued a report on the topic, which concluded that there was "no scientific evidence for risks of adverse systemic effects," and that "the current use of dental amalgam does not pose a risk of systemic disease."

But the report also noted a lack of data and a need for further study, so in 2012 SCENIHR opened up a "call for information" regarding a reassessment of dental amalgam. As Focus noted at the time, among the committee's concerns was whether dental amalgam is in fact safer for use in patients than its emerging alternatives, which SCENIHR said had not been extensively studied.

New Preliminary Report

SCENIHR's new preliminary report, which was passed by the committee on 26 August 2014 and opened for public comment on 9 September 2014, is similar to its 2008 report in several important ways.

Notably, the report does not observe any cause for concern with dental amalgam products.

The key passage in the report is this:

Local adverse effects in the oral cavity are occasionally seen with dental amalgam fillings, including allergic reactions and an association with clinical features characteristic of lichen planus, but the incidence is low (< 0.3%) and usually readily managed. Regarding systemic effects, elemental mercury is a well-documented neurotoxicant, especially during early brain development, and inorganic mercury also constitutes a hazard to kidney function. The presence of dental amalgam has been suggested to be associated with a variety of systemic adverse effects, particularly developmental neurotoxicity as well as neurological and psychological or psychiatric diseases. However, the evidence for such effects due to dental amalgam is weak.

The report also cautions against avoiding dental amalgam products in favor of the use of alternatives, such as resin-based composites, glass ionomer cements, ceramics and gold alloys. Some alternative materials can release bisphenol A, which is known to also cause "negligible risk" in patients, the report adds. Other materials have not been subject to rigorous study.

Ultimately, the report concludes that current evidence "does not preclude the use of either amalgam or alternative materials in dental restorative treatment," but that further study should be undertaken to evaluate the neurotoxic effect of dental amalgam and the potential toxicity of alternative materials.

The report comes several years after US regulators announced they, too, were evaluating dental amalgam and expected to have a new guidance issued by the end of 2011. No policy has yet been released.

SCENIHR Report