The Difference Between an Alloy and an Amalgam - It's Thermoelectric!

You're beginning to sound desperate Paul.

The reason why I keep returning to these newsgroups with the same old questions is because those questions have never been answered.

I recognise that people like you and Jim Pennino are able to convince yourselves that you have answered my questions, but you are mistaken. All you ever do is simply make up excuses for ignoring them because you don't know what the answers are.

Olin Perry Norton even appeared to have convinced himself that he had conclusively dealt with my questions by asking me one of his own which I couldn't answer!

How obtuse is that!?

Some of the earliest questions I posted to sci.med.dentistry were concerned with the physical properties of dental amalgams, and why it appears that properties such as their electrical conductivity and magnetic susceptibility had ever been measured. And those questions are still not resolved today.

I still bother to check. (I doubt very much whether any of you guys ever do.) And on a recent search I found a paper with the following title:

"Magnetic susceptibility and electrical conductivity of metallic dental materials and their impact on MR imaging artifacts"

- the summary of which can be seen at:

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I was sufficiently interested to pay the online fee to buy the complete article (see, I'm not such a cheapskate after all!), and do you know what I discovered? I discovered that the "amalgams" which the paper claims to have tested were not amalgams at all. They were simply samples of the various ALLOYS which are supplied to dentists for mixing with liquid mercury to form amalgams.

As it happens, two of those alloys do have some mercury in them - Starfill NG2 (3% Hg) and Ana 2000 Duet (2% Hg). However, despite their mercury content, these materials are NOT amalgams. They are ALLOYS. Dentists will appreciate perfectly well that you can't make amalgams with those proportions of mercury. These materials would have been formed by mixing ALL of the constituents (Ag 70%, CU 15%, Hg 3%, Sn

12%; and; Ag 43%, Cu 25.4%, Hg 2%, Sn 29.6%, respectively) in their molten states, i.e. at a temperature well above room temperature, and then allowed to cool at controlled rate.

The other "amalgams" tested, i.e. those with 0% mercury content, were not amalgams either, they too were ALLOYS (Safargam Plus, Safargam NG2, Safargam Special and Ana 70 Duett).

These alloys are purposely formulated for use in amalgams. It may make sense therefore to refer to them by the term "amalgam alloys", in which term the word "amalgam" serves as an adjective.

But they are NOT amalgams. And in the physical world, regardless of what anyone calls them, they do not accurately represent the physical composition of any material that would be found in anyone's mouth in the form of an amalgam dental filling.

The discovery of this paper therefore does not answer any of my questions regarding the physical properties of amalgam fillings.

On the contrary, it raises more questions.

Such as, if someone can get a Phd measuring the electrical and electromagnetic properties of the alloys used for mixing amalgams, why hasn't anyone bohered to do the same with samples of actual amalgams (i.e. after the alloys have been turned into powder and mixed with liquid mercury to form the actual amalgams which are placed in peopl's teeth.)?

The same paper also presents the results of measurements for a range of other metal alloys, those used for crowns, bridges, braces, etc,.

So we have the properties of electrical conductivity and magnetic susceptibility for just about every type of metallic material that dentists place in people's mouths, and for the ALLOYS used for mixing amalgams, but NOT for the mixed amalgams themselves.

And with regard to the actual amalgams themselves, i.e. as they appear in people's teeth, we are still ignorant.

How do you explain that?

And don't tell me that it's up to me to do the measurements myself.

That's just the same old excuse that you always use simply to avoid the question.

Keith P Walsh

Reply to
Keith P Walsh
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(snip--sorry).

I'm sure it's possible. I've watched for years as the denizens of sci.materials and perhaps sci.physics have encouraged you to conduct your tests. You can try it with plutonium, for all I care. I'm not using gallium, and I'm neither a physicist nor a metallurgist. And I'm not going to use gallium "alloys" in my practice. You should know though that I'm the type of guy who tests 9-volt batteries by touching them to my tongue. Maybe that's my problem right there.

Steve

Reply to
Steven Bornfeld

using gallium,

How about mercury amalgams?

Do you use them?

(And remember, it's NOT a pleonasm.)

Keith P Walsh

Reply to
Keith P Walsh

Take it up with Webster:

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Reply to
Mark & Steven Bornfeld

Like I said, it's a common misconception.

Reply to
Keith P Walsh

whether or not =3D whether or not whether

Is human tissva a superconductor--in the relevant band? That is, not in the picovolts-microvolts of the nuclear radio and aqveose ionic background, but in the millivolts of lone metals, which the human body is not?

Yes. And reception doesn't happen either.

That's a cretinose argument for thome who can't add. If there's a damping mekanism for stronger signals, the output still must show up somewhere.

A static magnetic field is itself born of el=E8ctric currend, and would need to feed another body to make another, and no longer stay static.

Which I like to call IC (AC + DC), intermittent currend, with one sign and on one side of the baseline.

[snip]

It was pap.

[snip]

-Aut> In reply, first of all, can I take it that you agree with my

whether or not =3D whether or not whether

Is human tissva a superconductor--in the relevant band? That is, not in the picovolts-microvolts of the nuclear radio and aqveose ionic background, but in the millivolts of lone metals, which the human body is not?

Yes. And reception doesn't happen either.

That's a cretinose argument for thome who can't add. If there's a damping mekanism for stronger signals, the output still must show up somewhere.

A static magnetic field is itself born of el=E8ctric currend, and would need to feed another body to make another, and no longer stay static.

Which I like to call IC (AC + DC), intermittent currend, with one sign and on one side of the baseline.

[snip]

It was pap.

[snip]

-Aut

Reply to
Autymn D. C.

It was not dereacted or dedissolved.

a composite

More unhappy than, say, piezoel=E8ctric chewing effects within the CEJ?

-Aut

Reply to
Autymn D. C.

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