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Amalgam fillings - really bad or not that bad?

  1. May 30, 2006 #1

    I am reading various articles online about the amalgam fillings and am quite shocked on the degree of variation of opinions from "professionals" on weather amalgam fillings are a major health hazzard or not. From what I could gather there are 3 camps. 1st camp says that they are a major health hazzard, that the amount of mercury in one filling is enough to posion all the fish in a small lake, that people with amalgam fillings are cronically poisoned with mercury and all that nasty stuff that comes with the package. 2nd camp says, yes that are toxic for body but the amount one is exposed by the fillings is minimal - you get more mercury from eating tuna than the fillings themselves. But the fillings should be banned not because of the health hazzard but because they pose serious environmental hazzard when they are disposed etc. The 3rd camps say they are perfectly safe, since they are used for more than 150 years and there arent any obvious side-effect deteced. Something like that.

    That makes me think that none of this people made any serious scientic study of the matter. Like 3 people would be watching a ball fall from a heigh of h meters and the question asked is how much time does it take for the ball to fall down. Guess these medical studies vary depending on who funded the research. Should the funding from people who are determined that the ball falls really slow they come to the conclusion that it takes t = h^2 * g time for the ball to fall down. On the other hand should they wish to show that balls falls down really fast then they would say that it takes t = sqrt(h/g) time for the ball. The most extremist would just state that ball falls down instantly!?! Should all of this people conduct a totaly scientific experiment they all would come to the matter that it takes exactly t = sqrt(2*h/g) time for the ball to reach the ground provided that the air resistance is neglected, should the air resistance be included then t = .. etc. Soo the opinion would be unanimous.

    How can there be such a "variation" in opinions? I ask this question here becose I trust "science" people. Since in science - scientific truth is what matters above all else. What are your opinions on this matter?
  2. jcsd
  3. May 30, 2006 #2


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    All I can do with this is to give a counter example. My wife works for a Dentist. At times, people have come to him to have their mercury fillings removed and replaced. Even though doing so would line his pockets, he tells them that is unnecessary, and that he would advise against it.
  4. May 30, 2006 #3


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    The only studies on such a topic would be epidemiological, which by their nature, are not controlled well. The best you can do is hope to find age-matched people who never had any fillings at the time when mercury fillings were used and see if they differ in any health problems from those with mercury fillings. The problem is that if you never needed a filling in that time, it could be an indicator that your overall general health was better too, either through better preventative care or the luck of the genetic draw.

    Likewise, with biological studies of any kind, and especially with epidemiological studies, the results are not always clear-cut. It's hard to sort out other risk factors, and you have to deal with individual variation. It's much easier to create a vacuum and drop a ball and measure the time it takes to drop with no other variables affecting it than it is to measure something in a population of people who have the freedom to live their life in their manner of choosing. This means that when you get results that are not clear-cut, there conclusions drawn from them can be much more open to interpretation. Usually, one tries to look at a question from multiple directions and in multiple populations before a sufficient body of evidence exists to start drawing stronger conclusions based on common patterns in all the studies rather than the results of just a single study.
  5. May 31, 2006 #4
    Thank you for the replies.

    Well my point was that there shuldnt be such a huge difference of opinions. They are of a magnitude that is equivalent to the difference of resistance of a conducting material compared to a non-conductive material.

    I didnt have in mind a very sofisticated epidemiological study. I would propose a bit simpler study.

    Take n dentists out of which they have at least i patients that have no amalgam fillings but have an appointemnt to have them done. The experiment would be as follows: monitor n*i patients before the filling(s) are done - that includes monitoring the levels of metals in the body including mercury in the blood, urine, breath, and saliva. That would give an estimate of the level prior to fillings. And then monitor the patients for 1 week after the fillings are done. Since there are 3 camps there would be 3 hypothesis: 1st hypothesis would be that the mercurty levels in the body would skyrocket after the fillings are done, 2nd hypothesis would be that the levels would be slighty elevated but nothing serious after, 3rd hypothesis would say that there should be no difference after.

    Now that ough to be a valid indicator weather or not amalgam fillings affect the biochemistry of the body after the fillings are done.

    The second step would be to have the levels analysed by a few good toxiologist. That would be a pretty decent experiment if you ask me. Sadly I couldnt find any published details of studies regarding amalgam fillings online. Just a bunge of articles that quote different studies.
  6. May 31, 2006 #5
    It is not advised to handle mercury with bare skin. Why would it be ok to have mercury as a permanent resident in your mouth?

    If its in your teeth, you are in contact with it. This doesn't take a 2 million dollar study to figure out whether or not its good or bad for you.

    For a list of symtoms see:

    The Poisoning of Minamata (Japan)

    http://www1.umn.edu/ships/ethics/minamata.htm [Broken]
    Last edited by a moderator: May 2, 2017
  7. May 31, 2006 #6


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    There are serious scientific studies on this subject. Here are three I found
    just in Apr 2006 issue of JAMA (Journal of the Americal Medical Association)

    Here are some more references you check out, they were given
    in the following article:
  8. May 31, 2006 #7


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    In dental amalgam, the mercury is incorporated as part of the compound material, and is not as freely available as if you were just handling pure mercury with your bare hands.

    From:http://www.ada.org/prof/resources/positions/statements/amalgam.asp [Broken]

    Quackwatch has a good explanation too. http://www.quackwatch.org/01QuackeryRelatedTopics/mercury.html
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  9. May 31, 2006 #8


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    In his schooldays (1960s), my dad had ended up with a mouthful of mercury when mouthpipetting it in the lab (safety standards were terrible in those days). No apparent ill effects. He has an IQ over 170.
  10. May 31, 2006 #9
    Sorry, apparently I put the wrong link with "see list of symtoms". But, Minamata is a fairly obtuse symtom.

    Here's a better description:


    And here is an article perfectly suited to this thread from the Journal of the American Medical Association (JAMA). Please read this and critique if you have the time!


    I realize that the mercury in compound fillings is part of the compound and not "pure mercury". It is however, 50% of the amalgam... along with silver and small portions of other metals.

    This amalgamation and the process of amalgamation does not change the toxicity of mercury... it only bonds it to some other elements like silver. Upon "gassing off" in the mouth, the mercury remains a toxic threat and a risk to overall health.

    Although mercury/silver amalgam is the most cost effective and one of the most maliable yet strong materials discovered (in the 1700s by the Chinese) to fill a cavity........ these arguments resemble the sort of argument that the Romans might have used to justify transporting their drinking water through lead piping. And we know the rest of that story. koo:surprised koo
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  11. May 31, 2006 #10
    IQ of over 170!!!... this is quite possibly a symtom of mercury-induced neurological hyperactivity!

    Unless your dad was mouthpipetting mercury everyday he does not make a good subject of study with regard to the effects of amalgamated mercury residing in a person's oral cavity 24/7.

    Don't get me wrong. I believe the old "what don't kill ya, don't kill ya..." type of reasoning. You know... like how you need a bit of arsnic every week to live through a full dose if it happens... and so on.
    Last edited: May 31, 2006
  12. Jun 1, 2006 #11
    Thank you very much for the replyies.

    "...did not, on average, have statistically significant differences..." yes we all love statistics.

    But anyway, guess the camp 2 is correct. Thanks again.
  13. Jun 1, 2006 #12


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    Hmmmm déjà vu :uhh: ........ (my last post - 1st ref.)
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  14. Jun 1, 2006 #13


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    No, I know it's just an anecdotal one-off thing. Just throwing it in there, since it seemed half-way relevant.:biggrin:
  15. Jun 1, 2006 #14
    Oops. I thought things felt duplicated today!... my apologies Ouabache.

    I certainly can't argue with the JAMA party paper since they have done the study and I haven't. I'll have to bow to the research and personally avoid toxic poisons like mercury and floride on my own. There are other poisons I'd rather expose myself to at any rate.
    Last edited: Jun 1, 2006
  16. Jun 2, 2006 #15


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    Your first statement is not necessarily true. If we are defining toxicity in terms of what deleterious effects the mercury will have to the exposed organisms, one major factor in this is bioavailability. In other words, in its current state how much of the toxicant in question is absorbed and interacting with the system. In this case, since it is bound in the amalgam, it has little chance to accumulate to toxic levels and elicit damage. Another example of this would be if I gave a person a capsule containg a lethal dose of cyanide that was coated in a material that could not be digested by the gi tract. Obviously the cyanide is still toxic, but it will not harm the person because it was not available.

    Another interesting aspect of this was brought up by the Minamata incident you mentioned. This was a tragic event the occurred in Japan when numerous people died or were seriously affected following the consumption of shellfish from the waters surrounding their home harbor. The mercury was dumped into the harbor by industrial processes and ended up in the sediments. This mercury in its metal ion state is indeed toxic, but not particularly so. In the sediments it was methylated by certain bacteria, which made it much more soluble and available for accumulation by shellfish and other animals. Once these were ingested the more toxic methyl mercury exacted its toll on the people. Very unfortunate situation, but again stressing that not all poisons are created equal. Perhaps if the people had only been exposed to the industrial waste mercury, things wouldn't have been so bad (pure speculation).
  17. Jun 2, 2006 #16
    I see what you are pointing out. That's fantastic information! So where I say the toxicity doesn't change in an amalgam you say the exposure to that toxicity is measurabley less than were it fully exposed as methyl mercury.

    I suppose my inclination is that if you have mercury in your mouth... you have mercury in your mouth and mercury is a class (x) toxin (effects will vary from person to person). If there is a viable alternative to having mercury in your mouth it sounds as though it would be a reasonably better choice than having a highly toxic metal firmly embedded in one's skull.

    I know the dental physicians who support this technique do so out of concern for the general populice. However, where one hand of the dentist offers the composite filling as an alternative... the other hand is defending the amalgam program. I guess that's marketing.
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