nos-trum. pronunciation: \nos'-trum\. noun. Etymology: Latin, neuter of noster our, ours.
1. a medicine of secret composition recommended by its preparer but usually without scientific proof of its effectiveness.
2. a usually questionable remedy or scheme.
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Sunday, December 19, 2010

Got Mercury? In Your Dental Fillings, That Is.

An FDA panel looked at allegations that the mercury content of amalgam used in dental fillings is hazardous.

That the mercury in dental fillings (the filling material is called amalgam) is harmful, has been a recurring theme; there are groups organized around the effort to lobby against mercury in dental use.  So far, the data hasn't been supportive. 

Hailed as a victory by the anti-amalgam crowd ("the myth of safety...has been destroyed" said one advocate, quoted in the USA Today Health blog, Dec 18) the FDA panel has just agreed to do some research into the question.
"The panel, convened by the U.S. Food and Drug Administration to look into the safety of amalgam dental fillings containing mercury, advised the agency Wednesday to reevaluate the use of the material in children and pregnant women."
Does that sound like the FDA has concluded there's a hazard?  It says "reevaluate."  I guess that's a victory of sorts, but not so much for the advocates, but for science.  Clearly, we want to be very careful.  Mercury accumulates in the body to some extent; it's possible that children and the unborn may be more vulnerable.

Amalgam has been looked at more than once.  There isn't much reliable research that amalgam causes health problems.  Large scale studies don't give a definitive answer.  Much of the testimony before the FDA came from individuals.  It's reasonable to hear somebody's unsubstantiated belief, and take action to investigate.  But it's not reasonable to conclude that individuals who have neurologic or kidney disease were harmed just because they have amalgam in their mouths, when millions of other people have amalgam and aren't harmed.  It's possible those individuals have mistaken beliefs...which they will never be convinced are false.  Psychologically, it's impossible for some people to accept that they get ill for reasons that don't include influences outside their own bodies.

Over a year ago, the FDA changed mercury from a class I device to a class II.  This directs more controls over its use.  A few countries have banned the use.  Concerned groups have questioned the way FDA does its risk assessment, as have other groups with other alleged hazardous substances.  The FDA has responded with a project to re-vamp how they measure risk.

But, there's also a plausibility issue with claiming harm from amalgam.  I read somewhere that it's estimated there's more mercury exposure over the years if you eat a tuna sandwich every month (on average) than from amalgam in your teeth.  Tuna contains a very low level of mercury (as do other foods).

And while mercury is released over time from the dental amalgam, the amount is tiny.  You are probably much more exposed to several hundred other metals and volatile organic compounds in your everyday life.

In any case, if the FDA accepts its panel's recommendation, maybe we'll get some definitive research done.  For now, I'm not having the...let's see, one, two, three...four fillings removed.

My dentist says that if people ask for non-metallic products (including no gold in crowns), he says OK.  But he also warns them that the substitutes don't last as long, and if they need to be re-done, it's on their dime.

And, he’s following the scientific debate.  If the science shows there is a hazard, things will change.

Doc D

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