Magnetic Susceptibility of Dental Amalgams



Dodging the question is also an answer, I guess..
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madiba

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snipped-for-privacy@thekraal.com (madiba) wrote:

Touching a doorknob after walking on shag carpet will cause far higher discharges, and this has no harmful effect on humans or nerve endings. And who is to say that the bound charge in an amalgam will even discharge at all? No mechanism for charge accumulation or discharge has been demonstrated, so claiming any health effects related to this requires a leap of faith.
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I guess you're the physicist, I had no idea the physics of the discharge had not been sorted out. The cabling (the nerves) are there for it to happen in an intact tooth. Needs to be tested.
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wrote:

Keith shuffles on the carpet and then touches an amalgam to the doorknob ,,,,,,, but watch out if someone is in the room beyond.

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Joel M. Eichen, .
Philadelphia PA
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wrote:

You're not comparing like with like here.
Static discharges of the type experienced after walking across a carpet occur at potentials of up to thousands of volts.
But the amount of energy dissipated by the discharge wouldn't light a flashlight bulb for any appreciable amount of time at all.
Everyday batteries which are able to drive a sustained current through a flashlight bulb filament and keep it lit for many hours do so with an operating potential of just a few volts.
The nature of the dissipation of the energies involved in these two situations is dependent on a combination of variables and is very different for each case.
That's why I keep making the point that in order to understand the nature of any dissipation of electrical energy due to the generation of electrical potentials by amalgam dental fillings it should be necessary to carry out experimental investigations to measure it.
And this would include establishing by physical measurement that there is no dissipation of energy at all.
It isn't enough to just rely on guesswork for answering these questions.
Shall I tell you why?
It's because your guesswork might be wrong, that's why.
And amalgam dental fillings are placed in children's teeth.

As far as anybody can tell this statement might be true simply because the experimental procedures which would be necessary in order to demonstrate such effects have never been carried out.
And in the absence of any scientific evidence of any kind regarding the matter then the only other logical possibility is that such investigations have been carried out but the results are not available.
Keith P Walsh
PS, enquiries concerning the electrical behavior of metal amalgam dental fillings can be found at:
http://book.boot.users.btopenworld.com/intro.htm
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Does anyone else get a mental image of the shrieking woman, "But think of the children!", when the bear came to Springfield in the Simpsons?
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And the energy stored/dissipated by an amalgam would be thousands or millions of times weaker. What's the capacitance of an amalgam -- a femtofarad? I rest my case; no harm done.
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I thought that a bunch of amalgams in series would light up a flashlight.
wrote:

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Joel M. Eichen, .
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So you are saying you need five amalgams to trigger one nerve ,,, I mean five nerves trigger one amalgam.
On Sun, 25 Jan 2004 00:52:40 +0100, snipped-for-privacy@thekraal.com (madiba) wrote:

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madiba wrote:

Chew on some tin foil. :-)
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cheers, Cecil http://www.qsl.net/w5dxp



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Amalgam is not a capacitor it can not hold charge. If it could we would use it instead of batteries. the 350mV if that number is accurate I do not know, represents a galvanic reaction between two or more metals. Depending on what the metals are a different "eddie type current" is generated. The problem is that in the human body everything generates a small potential difference which averages to zero Volts. Blood carrying iron moving through vessels passing through magnetic field of the earth will generate some type of current much higher than 350mV I would imagine. If you want to see this get a digital voltmeter hold one wire in one hand and the second wire in the other hand. You will see a potential difference that fluctuates that is all. even if you took amalgam scrap you can not attach one electrode to silver and the other to murcury in amalgam to measure this voltage the reading will be zero volts. There is no way of measuring the current in Amalgam in someone's mouth and attributing it to causing events in the brain. This whole topic is pointless at this stage on the game.
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On 24 Jan 2004 20:45:02 -0800, snipped-for-privacy@yahoo.ca (Alexander Vasserman DDS., BS.) wrote:

We do. How else would the radio inside my tooth work?

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On Sun, 25 Jan 2004 23:06:32 +0900, H. Dziardziel

It has been known for more than 160 years that metals, mixtures of metals, and dissimilar metals in contact with each other are able to dissipate electrical energy to their surroundings as a result of their thermoelectric properties, and that it is not necessary for there to be any electrolysis taking place in order for this to happen.
For an elementary description of the thermoelectric effect go to:
http://book.boot.users.btopenworld.com/thermo2.htm
Keith P Walsh
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Ummm, the thermoelectric effect requires two different metals in contact.
The net thermoelectric effect voltage of a discrete lump of any homogenous metalic substance is zero.
If the only metal is amalgam, how could you have a thermoelectric effect?
Amalgam filling touching a gold or silver filling?
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Jim Pennino

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writes

And a temperature difference.

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Richard Herring

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On Sun, 25 Jan 2004 23:48:57 +0000 (UTC), snipped-for-privacy@specsol-spam-sux.com wrote:

Well for a start this statement is factually incorrect.
The Penguin Dictionary of Physics gives the following description of the "Kelvin (or Thomson effects)" under the general heading "Thermoelectric Effects"
""A potential difference is developed between different parts of a single conductor if there is a temperature difference between them; for a temperature difference dT between two points, the e.m.f. in this element is udT (u = greek letter mu) where u is the Thomson coefficient."
So you were wrong about that.
What complicates matters further in the case of dental amalgam is that dental amalgam is not in fact a "homogeneous metallic substance".
Dental amalgam is an inhomogeneous mixture of dissimilar metals. See:
http://book.boot.users.btopenworld.com/setting.htm
So you were wrong about that too.
And one might expect the thermoelectric behavior of this material to differ from that of a homogeneous metallic substance accordingly.
You can get an idea of the kind of thermoelectric processes occuring when an inhomogeneous material is subjected to a temperature gradient at:
http://www.finoag.com/fitm/n6.html
(Fig. d is particularly instructive.)
Apparently, not only does the temperature gradient induce thermoelectric eddy currents in the material giving rise to the localised electromagnetic effects shown, but the reverse effect whereby an applied electromagnetic field gives rise to induced eddy currents and associated temperature gradients is also possible.
Dental amalgams are subjected to thermal gradients all the time.
And amalgam fillings are placed in children's teeth.
I believe that the thermoelectroic properties of dental amalgams should therefore have been measured.
And I am confident that I am right.

Amalgam is an inhomogeneous mixture of dissimilar metals.

Not necessarily.
It has been common practice for dentists to screw metal alloy retaining pins into the root sockets of patients' teeth and encase the heads of the pins in amalgam, thereby providing further opportunity for thermoelectric effects to occur at the interface between the amalgam and the alloy.
I believe that the only scientific way to determine whether or not these effects are significant is to measure them.
And again I am confident that I am right.
Keith P Walsh
PS, enquiries concerning the electrical properties of dental amalgams can be found at:
http://book.boot.users.btopenworld.com/intro.htm
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Keith P Walsh
First of all the letters are talking about deal with a galvanic reaction not a thermoelectric effect which you are describing. These are 2 different things. I gave you my comment of the Galvanic reaction earlier. As far as your thermoelectric effect, that requires a thermal gradient meaning one end of the amalgam filling must be heated and the other end cooled at the same time. In the mouth that can never happen even if the patient eats ice cream after drinking hot coffee. The gradient needs to be applied at the same time. You are just trying to confuse the issue by bringing in different effects of electromagnetics. Amalgam is a homogenous mixture of several metals.

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On 30 Jan 2004 20:28:15 -0800, snipped-for-privacy@yahoo.ca (Alexander Vasserman DDS., BS.) wrote:

When Bates, Baker and Meakin of the University of Nottingham in the UK wished to investigate the magnetic susceptibility of a NON-homogeneous material they chose to use "amalgams of metals in dilute solution in mercury".
Are you saying that they made the wrong choice?
Keith P Walsh
PS, the abstract from the resulting paper reads:
"A description is given of a new apparatus and technique for the examination of the magnetic susceptibility of a non-homogeneous material, with particular reference to the investigation of amalgams of metals in dilute solution in mercury. An important feature of the apparatus is that the electromagnet has one pole tip with a cylindrical surface and one pole tip with a plane face, so that when an amalgam is placed in a vertical tube suspended from a torsion balance, each portion of the amalgam is exposed to the same value of the gradient of H2 in the direction along which motion of the tube is possible; consequently, measurements can be made with amalgams which separate on standing."
- and the whole thing can be purchased via;
http://www.iop.org/EJ/abstract/0959-5309/52/4/301 /
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Where's the temperature difference in the amalgam? None? Oh well, you're wrong again. Why don't you figure out mu for an amalgam and then see what kind of dT you would need for it to fry a person's neurons. This is electromagnetics, and we need to see equations and hard numbers, not haphazardly used definitions which have no applicability.
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wrote:

Temperature gradient is ubiquitous in Nature.
Dental amalgams are subjected to temperature gradients all the time.
The latest thermoelectric wristwatch batteries are able to generate voltages of up to 1.5 volts from a temperature gradient of only 1K. See:
http://www.natureinterface.com/e/ni03/P045-049 /
Of course, one might not necessarily expect an accidentally constructed thermoelectric battery to operate with the same efficiency as a purpose-built one.
Nevertheless, levels of temperature gradient much greater than 1K are commonplace in the human mouth.

Material properties are not "figured out".
They are measured.
I would expect any electrical potential arisng in a single homogeneous metallic material due to its Thomson coefficient to be "small".
What makes the situation more complicated in the case of dental amalgam is that dental amalgam is not a single homogeneous material, it is an inhomogeneous mixture of dissimilar metals. See:
http://book.boot.users.btopenworld.com/setting.htm
And it is generally the case that thermoelectric effects are much larger where there are two or more dissimilar metals in contact with each other.
The electrical potentials, currents and energy dissipations involved in human neurological processes are also "small". (But not too small to be measured.)
What is not in doubt here is that it has been demonstrated experimentally that amalgam dental fillings generate electrical potentials with magnitudes of up to 350 millivolts. See:
http://book.boot.users.btopenworld.com/dutch.htm
However, it appears that two questions which still remain unanswered are, firstly, exactly how do these potentials arise, and secondly are they able to dissipate electrical energy through the nerves in people's heads?
With regard to the first question, dentists confidently tell us that newly placed amalgam fillings quickly acquire a layer of metal oxide on their exposed surfaces as the result of a small degree of electrolytic corrosion, and that this layer adheres permanently to the surface thereby preventing further electrolysis from taking place.
(I have no reason to doubt that this is the case.)
So for an answer it might be necessary to consider other phenomena by which electrical potentials are induced in metallic materials. And two which come to mind are thermoelectric phenomena and electromagnetic phenomena (which we know are linked with each other).
Unfortunately (and some might suggest inexplicably) it appears that neither the dental profession nor any other organisation in the world knows anything at all about the thermoelectric or electromagnetic properties of dental amalgams.
I wonder if this might be due in some part to the answer to the second question.
(Remember, if it can be shown that thermoelectric and electromagnetic phenomena are between them not able to generate electrical potentials as large as 350 millivolts in dental amalgams, then this does not necessarily mean that this figure is false. It would simply make it necessary for us to conclude that we still DO NOT understand where it comes from.)
Keith P Walsh
PS, This thread started with an enquiry about the magnetic susceptibility of dental amalgams.
In view of the fact that dental amalgam is an inhomogeneous mixture of dissimilar metals, would you expect the magnetic susceptibility of the material to vary from point to point within the material?
And, if so, would you expect to be able to establish scientifically that it is not possible to measure this variation without ever having bothered to try?
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