Faradaic Activity in Dental Amalgams



Yup, to say nothing about pigeons with amalgam fillings ......
They are "DRAWN TO" the power lines .....
I always see them sitting around there .......
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No- the danger would be due to relative motion of the teeth with respect to the body- this danger is at a maximum when engaged in political doubletalk. Since the life span of a politician is normal, it appears that the risk is negligable- too bad! :)
--

Don Kelly @shawcross.ca
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Particularily when one train leaves Chicago at 65 mph and one leaves Denver at 55 mph.........
The answer in this years SAT is
c. 350 mV
carabelli
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It is stupid posts like this, that show the dentists think the dangers of amalgams are all a joke.
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I find the following suggestion pretty funny myself. I suppose this is why nobody takes any personal responsibilty anymore.
"The batteries in my teeth made me do it!"
"I am being controlled by aliens..."
"Low frequency radio waves are controlling my brain..."
Dear
The enclosed sheet shows how when a crude electric battery, such as a metal amalgam filling, is inserted into the tooth of a live human being, then the innervation of the head (through the upper and lower mandibles, tongue, sinuses, eyes, bridge of nose, ears and all the way back to the pons) provides a network of circuitry capable of dissipating the potential of the battery in the form of an electric current.
It must be recognised that each individual in society has their own unique array of tooth batteries and these vary from person to person with regard to size, number and time of life when each battery was fitted/removed.
It is my firm belief that it is the presence of these batteries in peoples mouths which is causing many to feel that they have inadequate control of their own lives.
Could you please supply me with any evidence you have which contradicts this belief.
Kindest regards,
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snipped-for-privacy@comcast.net wrote: (snip)

Sorry, it is not my job to contradict your beliefs (and I can't imagine any evidence for the absence of such a hypothetical effect that would change your mind).
You are welcome to any beliefs that suit you, as long as you don't try to force me to believe.
It is your job to support your beliefs with evidence and logic, if you expect to persuade any reasonable person that your beliefs are valid.
You are also free to skip this part and blame the world for not being inspired by your unfounded presuppositions.
That would put you in large company.
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Do you know if experimental investigations have ever been carried out to measure the response of the neuron to any "net current and voltage,fields, capacitance, etc produced externally by the amalgam"?
Keith P Walsh
PS, it has been demonstrated experimentally that metal amalgam dental fillings generate electrical potentials with magnitudes of up to 350 millivolts. See:
http://book.boot.users.btopenworld.com/dutch.htm
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yes
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Keith P Walsh wrote:

A better question would be what experiments have been carried out to measure any neural response to electrical input. For example if someone subjected a tooth nerve directly to a sinusiodal voltage the nerve couldn't distinguish between that and an amalgam causing the voltage. If you did such an experiment you could then draw conclusions about what type of electrical output the amalgam would require to affect the nerve. In fact electrical pulp testing does use this principal, but the voltage lead is far away from the tooth nerve (as opposed to an amalgam which could be placed very close to the nerve).
As I said before basically the maximum output from the amalgam is going to be set by the available EM energy traveling in space, as far as electromagnetism is concerned.
I suppose you could take an antenna (by itself without a power source) and connect it to a tooth to simulate an amalgam. I think an antenna or (amalgam antenna) has to be impedance matched to transfer EM energy efficently though so the exact resistnce of the tooth/neuron circuit it is connected to would be important. you could also vary the size of the antenna to see if it picks up different wavlentghs.
You could also take an amalgam and substitute it for an antenna and see if a radio is able to amplify the EM waves it picks up.
You could also take an amalgam and place it in an experimental circuit where it is generating some galvanic effect. you could Add an exteranl Em field and then measure any changes in the circuit current to see if the EM field has any affect on the electrical properties of the amalgam. there is an effect called he hall effect where an external field affects the elecrtical properties of a semiconductor. if indeed you found that was the case for certain amalgams mixed a certai way you could then design an experiment where you subjected a nerve to a voltage (from a voltage generator) that mimiced the combined galvanic/em modulated output of the amalgam, you measured.
As you can see there are many experiments you can perform by swapping out components and treating the circuit components as "black boxes".
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Yes, go see Prof. XXX in the physics department at your local college/university.
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Keith P Walsh wrote:

The only difficulty in assigning a measured value of resistivity to amalgam is that it is not a single material but a whole class of materials. Many different compositions are possible (similar to but the range of alloys possible that might be called solder). But the resistivity of any specific mixture is ordinarily measurable and all are metallic conductors.
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wrote:

It is the opinion of our fellow newsgroup contributor billkatz that:
".... because of the high resistance of amalgam, it cannot truly be classified as a conductor."
Would you disagree with him?
Do you know if anyone has ever measured the electrical resistivity of a particular dental amalgam?
Keith P Walsh
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Keith P Walsh wrote:

I just did.

Well, I just touched the two leads of my ohm meter to one of mine, and the result was indistinguishable from just touching the leads together (0.3 ohms, in each case). Such a test doesn't quantify the resistivity very well, but it puts an upper bound on it. It is definitely not only a conductor, but a good one.
From: http://dsp-psd.communication.gc.ca/Collection/H46-1-36-1995E.pdf "Dental amalgam is a mixture of metals consisting of approximately 50% metallic Hg, by weight, mixed with an alloy containing varying amounts of silver (up to 70%), copper (up to 30%) and tin (up to 30%), among other potential components (Berry et al. 1994)."
From: http://www.du.edu/~jcalvert/phys/mercury.htm#Amal "Mercury has the property of dissolving nearly all metals, forming liquid or solid solutions called amalgams. It amalgamates well with gold, silver and tin, but does not dissolve iron or platinum. This is the reason iron flasks and iron vessels are used to refine mercury. Curiously, the electrical resistivity of an amalgam may be less than that of the pure metal, which is not usually the case for alloys."
From: http://www.du.edu/~jcalvert/phys/mercury.htm#Prop "The electrical resistivity (of mercury) is 98.4 μΩ-cm."
As I said before "amalgam" does not have a single value of resistivity, because it is a rather arbitrary mixture of elemental metals, and each recipe has a different resistivity.
From: http://en.wikipedia.org/wiki/Mercury_ (metal) Mercury easily forms alloys with almost all common metals, including gold, aluminium, and silver, but not iron. Tellurium forms an alloy also, but it reacts slowly to form mercury telluride. Any of these alloys is called an amalgam.
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<snip>
Sigh. You beat me to posting. I got 0.4 ohms.
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yes
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Keith: I'll write this backwards so maybe you can understand it easier:
!!!!tnemtraped scisyhP egelloc lacol eht enohP
OK SP
--
Take out the TRASH to reply

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On Sat, 10 Sep 2005 17:29:00 +0000 (UTC), Keith P Walsh

billkatz is incorrect. My mercury amalgam fillings conduct just fine.

Nop.e, but I am not a dentist either.

the softrat Sometimes I get so tired of the taste of my own toes. mailto: snipped-for-privacy@pobox.com -- Dough, the stuff, that buys my beer, Ray, the guy that tends the bar, Me, the guy, who drinks my beer, Far, the distance to the bar, So, I think I'll have a beer, La, Laa lAA lAh LaH LAA LAAAH! Tea, no thanks I want a beer, which brings us back to Dough Dough Dough!
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wrote:

True, that's why dental filling materials are in a state of flux.
Joel
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Nah. Magnetic flux is what you use with iron-cored solder.
--
Richard Herring

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But when challenged to go to the physics department of your local college/university where they could easily put this question to rest for you, you continue to ignore this avenue of research

yes
see above. the question is: having provided you with an experimental procedure by which the electrical resistivity of a typical dental amalgam CAN be measured, why do you refuse to perform the experiment?

The physics department of your local college/university.

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