Less than 18 months after proclaiming amalgam dental fillings safe, the U.S. Food and Drug Administration Tuesday begins rehearing evidence on one of the most controversial topics in dentistry - whether these so-called silver fillings are safe.
Professional organizations representing dentists say the amalgam - about 50 percent liquid mercury in a composition of powdered copper, tin and silver - is not only safe, but also one of the most effective and inexpensive dental products on the market.
The amalgam has been used in the United States and elsewhere for more than 150 years.
But four consumer advocacy organizations have mounted a challenge to the FDA's March 2009 ruling. They cite a range of new studies that point to neurological conditions and even Alzheimer's disease as consequences of some people's dental work. The organizations are asking the FDA's dental-products panel to, at the very least, reclassify the amalgam to bar its use in pregnant women and children. The organizations, however, have stated publicly they would prefer to see the amalgam banned. Denmark, Sweden and Norway have banned the use of the fillings. Other countries - Canada, Germany, France and Italy - have restricted its use.
The groups are also accusing the FDA and the American Dental Association of maintaining too cozy a relationship with the dental products industry. They note that FDA Commissioner Margaret Hamburg is a former official with Long Island-based Henry Schein Inc., a dental amalgam company, and divested her Schein stock one day before the agency's amalgam ruling last year.
Nancy Stade, deputy director of policy in the FDA's medical device division, said panelists will weigh evidence from several scientific studies during the two-day meeting in Maryland, which ends Wednesday. Speakers who say they've been harmed by their fillings, Stade said, will be allowed to speak for four minutes.
Denise Knight, 55, a Holbrook resident and former flight attendant, said she's been cleared to address panelists. Knight tells a harrowing story of what she believes was mercury poisoning that forced her to quit her job 10 years ago and left her too sick to return to work. The illnesses she attributes to mercury include severe memory loss, colon and heart problems, and breast cancer.
"My whole life was taken away from me," said Knight, who said her symptoms began when she had the fillings removed. Knight saw an alternative medicine physician who treated her over a three-year period with chelation therapy, an infusion treatment to purge lead from the blood. The treatment is considered offbeat by conventional medical standards.
Dr. Mark Feldman, executive director of the New York State Dental Association, who practices in Garden City, noted frequent challenges to dental amalgam over the years. Mercury is not released in a harmful elemental state from dental fillings, but as a vapor, he said. "I have it in my mouth and in my children's mouths."