Magnetic Susceptibility of Dental Amalgams

Which would be more likely since amalgam usage is dropping but 'psychiatric "medicine"' usage is rising.

Now if Keith P Walsh would just avail himself of some...

I am afraid your answer was too verbose for me to enjoy reading it. And it did not make a solitary reference to the littlr matter of the magnetic susceptibility of dental fillings, which is what I asked about.

[snip]

Franz

Relative to what?

[snip]

Franz

wow, two sets of mercury amalgam induced nut bars duking it out on the same NG. Should be an entertaining next batch of posts ...

MA Sonjariv (have followed the walsh posts for a couple years now - always the same - truly one of the better trolls frequenting sci dot NG's!)

Its even worse than this, can reach 350 billion picovolt. Shocking.

Mati Meron | "When you argue with a fool, snipped-for-privacy@cars.uchicago.edu | chances are he is doing just the same"

If you take into account quantum mechanics and string theory those amalgam voltage potentials extend into other universes ..........

So what? Are you claiming that an amalgam is a capacitor? Prove it. And even if an amalgam had some mechanism for accumulating charge, who cares? It won't hurt anything. You need to prove that either heating or arcing is occuring, and there is no way that 0.35 V is going to do the vicinity of a tooth.

What a crackpot claim!

So that's what happened to the Mars probe....

Someone else raised this point recently.

I think it's a valid question.

Being purely speculative about it, one might suggest that if the electrical potentials generated by amalgam fillings ARE able to dissipate electrical energy through the nerves in people's heads, then any neurological effect might be arbitrary in nature.

Put simply; it might make some people happy, it might make some people unhappy, and it might cause what are commonly referred to as "mood swings" in others.

However, speculation on its own does not constitute science.

We should need some kind of observed evidence to determine the degree to which any such kinds of influences occur.

For example, is there any significant level of "irrational fear" of going to the dentist in our society?

Is there any significant level of "irrational predilection" for going to the dentist in our society?

And other such questions.

Putting speculation aside, we know reasonably well for certain that metal amalgam dental fillings generate electrical potentials with magnitudes of up to 350 millivolts. See:

However, in addition to the fact that experimental studies to determine whether or not these potentials are able to dissipate electrical energy through the nerves in people's heads have never been carried out, it also appears that it is not fully explained as to how they arise.

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.

However, 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 generate electrical potentials 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.

It has also been known for more than 160 years that when an electrical conductor moves in an electromagnetic field an electromotive force is induced in the conductor, and that when a stationary conductor is subjected to a varying electromagnetic field then an electromotive force is again induced in the conductor.

According to the established principles of scientific understanding, in order to eliminate the possibility that the generation of these potentials is contributed to by the thermoelectric and/or electromagnetic properties of dental amalgams, it should be necessary to measure them.

Nevertheless it appears that there isn't anyone anywhere in the world who knows what the electromagnetic properties (including magnetic susceptibility) of dental amalgams are.

And it also appears that there isn't anyone anywhere in the world who knows what the thermoelectric properties of dental amalgams are.

(A dental amalgam is an inhomogeneous mixture of dissimilar metals, a typical example of which can be seen at:

It might be expected therefore that its physical properties should vary accordingly from point to point within the material. Establishing what influence, if any, that this variation might have on the electrical behavior of the material might also require experimental investigation.)

As things stand, anyone who wished to find out the extent to which the electrical potentials generated by the amalgam fillings in their teeth were compromising their ability to feel contentment would have to be satisfied with the only honest answer which the dental or any other profession could give: "I'm sorry we have no idea."

And amalgam fillings continue to be placed in children's teeth.

Keith P Walsh

Do you have any reason to believe that it could make people crave bagels and lox?

carabelli

So you are saying that monoamine oxidase inhibitors are actually baked inside the bagels and lox?

LOL!

- why not, until the science has been done anythings possible. OTOH the brain is used to recognising pain as the only message coming from the teeth, apart from slight proprioceptor activity. Why should it interpret the current produced by amalgams as something else?

Right, its the human tooth, not the auto welding shop.. No arcing needed, just a light discharge in the direction of the pulp/root. IIRC .07mV is enough to trigger a nerve.

He's worried about neurons on the other side of the cranial base, roughly the equivalent of my cell phone causing cancer in neighbors two blocks away.

carabelli

Interesting comparison. It could of course (say the pundits) if you use it to phone the neighbor on his cell phone.. But I digress. :-/ A better comparison would be to say its like causing your neighbours two blocks away to be sleepless by piping rap music to their home day and night via cable. The idea is the current produced by the amalgams goes via the dental nerves -> alveolar nerves -> trigeminal nerves -> the brain. I don't think its been proved to really happen, but why's the theory so difficult for you to understand, as a dentist?

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.

But what's generating the current? Little nuclear power plants inside the amalgams? If you touch one end of an AA battery to your tongue, you won't get zapped and the potential across the battery will remain at 1.5 V. Somehow a circuit needs to be completed, and in the case of amalgams there is no completed circuit.