Testimony During the Proceedings

On December 14th and 15th 2010, the Food and Drug Administration held hearings to determine whether further restraints were necessary in the use of mercury fillings in dentistry. The panel was comprised of dentists, toxicologists, statisticians, consumers, environmentalists, biomaterials experts. The chair of the panel was Dr. Marjorie Jeffcoat, former editor of the ADA Journal, and former Dean at the University of Pennsylvania School of Dental Medicine. The voting members of the panel were all dentists from academia.

Given that the ADA is the body that sanctions dental schools, and approves their curriculums, and that the ADA’s policy has been that mercury restorations are safe, this panel seemed a bit weighted on the ADA side. Also, if you watch the videos posted (listed below) you will note that speakers on the pro-mercury side were never interrupted by Chairman Jeffcoat, and all other speakers heard a countdown of seconds left. This was unnecessary because everyone knew they were limited to four minutes, and there was a light in front of us that went from green to yellow after three minutes, and turned red when there were ten seconds left.

My good friend, neighbor, and former President of the Academy of General Dentistry spoke immediately before I did, in favor of not limiting dentists’ choices of restorative materials. His speech was without interruption. My testimony immediately following Dr. Vincent Mayher was interrupted twice, as were the others who spoke out against mercury fillings. Dr. Amid Ismail, from Temple University was one voting member who seemed to be listening to reason. Dr. Joel White, from University of California and Dr. Jeffcoat appeared to be staunch in their resolve not to let any change happen.

Michael Fleming, a dentist from Durham, NC and Karen Rue, of Lafayette, LA (consumer representative) were both non-voting members of the panel and appeared to be pushing for change.

There were many pleas for resolution from individuals whose lives have been inexorably changed by mercury fillings (they felt).

For more, simply query mercury fillings & toxicity on any search engine, including YouTube.

Following two days of testimony from people on both sides of the fence, the panel met in open session to determine, at the FDA’s specific instruction, whether the following paragraphs needed to be rewritten, or altered in anyway.

Clinical studies have not established a causal link between dental amalgam and adverse health effects in adults and children age six and older. In addition, two clinical trials in children aged six and older did not find neurological or renal injury associated with amalgam use.

The developing neurological systems in fetuses and young children may be more sensitive to neurotoxic effects of mercury vapor. Very limited to no clinical information is available regarding the long-term health outcomes in pregnant women and their developing fetuses, and children under the age of six, including infants who are breastfed.

What followed was about four hours of people expressing opinions, but no solid basis for change was arrived upon while I was there listening. There was a reporter present who was blogging for DrBicuspid.com , a dental industry website, and her reports from Day one and Day two are quite extensive.

There are a lot of confounders that cause the release of Hg vapor on a daily basis from dental amalgam. (chewing, thermocycling, etc) FDA needs to stratify the exposures for different cohorts e.g. Children. They also want a proposed study by FDA to determine “What is the component of error in determining inhalation of Hg vapor?“

Inhalation physiology must be differentiated as a study variable comparing children and adults, which increases vulnerability of children. Age alone is not a determinant. Easily measured by FV 1 studies. There is no data studied for children under the age of 6. Salivary flow and bacterial population also need to be considered. Pregnancy and fetal exposure to Hg vapor needs to be given a lot of thought. Mercury and lead are much more harmful (synergistic) in a developing brain and in conjunction with one another. A panelist was uncomfortable with this sort of limitation, because many of the neuro-cognitive effects might not become evident for decades.

Need to take into account the long-term delayed effects from pre-natal exposure.

Genetics role - mthfr, apoe4, etc
Need to put COPD asthma and respiratory problems into the model
There is no way to build a model to determine the daily dose of exposure to Hg vapor exposure, because of so many unknowns. No way to do a model for maternal/fetal, and for children under age 3.

3. Can urinary excretion be used to measure as a biomarker? How should FDA measure it?

Urinary studies are the best we have, but we need better more advanced studies, but very expensive to do, and impossible to do in neonates. It is useful, but not by itself. The panel then wanted to know where fecal excretion fits it. Dr. Ann Summer, UGa, found that her studies in monkeys it correlated with blood & urine.

What other markers should be looked at? FDA needs to design clearance and bioaccumulation studies.

Consensus statement - newer studies need to be incorporated, sensitive populations must be included, along with genomic information.

Risk vs. Benefits – Hg filling survival is 10% better and less technique sensitive. Talked about the Casa Pia study a lot. It is what is used by pro-mercury individuals to support Hg safety. There are many faults with this study, not the least of which is the fact that symptoms often do not arise until over-exposure, which can often be 30+ years later.

The panel debated Efficacy vs. Safety.
There are gaps in the data, specifically with regard to MS, ALS and Parkinson’s data.

So to add to the debate, and her pro-mercury posture, Dr. Jeffcoat postulated that “Dental caries is an infectious disease, and can it not be interpreted from the outcomes that these sequellae are coming as a result of the disease?” This was very surprising to me, because Dr. Jeffcoat has always been a champion of women’s issues as they relate to dentistry. She was quite active in promoting the fact that gum disease needed to be dealt with more stridently in pregnancy due to the correlation with pre-term abortion, and low birth weight.

The panel wanted to know whether they were dealing with US or worldwide data?

The agency is tasked with protecting the health of US citizens directly, and worldwide as a side benefit. The best human studies have been hit hard the last two days.

It was proposed that in forthcoming increased labeling, that there may be some populations that are sensitive, and that there are a lot of things that we don’t know about mercury amalgam. The information needs to go both to the dentist and the patient. The consumer representative on the panel stated that most dentists wouldn’t bother reading the label. The panel appears to be moving towards much stronger labeling. A point was raised that the product information sheet language and placement thereof needs to be prominent. A reference was made to "black box labeling". Proposal that it not be limited to fetuses and children under 6.

Are there relationships between the use of amalgam and causal effects. Studies on pregnant women have not been performed. Its not safe for use by everyone. Dentists should consider them in patients who are pregnant or nursing, patients with neurological problems, nephrotoxicity. There must be precautions regarding safe handling and disposal.

Dr. Fleming felt that contraindications should be listed as such, and he is concerned about affirmations of safety in the face of no clinical evidence. There are definitely patients who are sensitive to mercury. The FDA representative indicated that unless contraindications have been discovered and published as part of a scientific paper, the FDA cannot label contraindications.

The following question was raised: How is it in the absence of data we can say that something is safe. In light of the stories the panel heard these two days, Dr. White felt there is nothing wrong. Jim Love, counsel for the IAOMT was given 30 seconds to refute this.

Consensus of the panel was that the FDA did not fully state the full truth on the statement in the box.

There should be a consideration for risk assessment for each individual getting a filling.

Much additional reporting was done this year as the publicity for this even was much larger than it was in 2006. The story was covered on NBC Nightly News, CBS Evening News with Katie Courik, The Washington Post, The Philadelphia Inquirer, The Boston Herald, and the Los Angeles Times to name a few. The reporting was quite balanced.

The panel did not vote on final conclusions, but several members stressed their wish to know more about the effects of mercury on certain subpopulations.

Joel M. White, DDS, MS, a professor in the division of biomaterials and bioengineering at the University of California, San Francisco, said he believed there is "clearly a subgroup of highly sensitive individuals where amalgam is contraindicated."