Either that or someone who has identified a gap in our scientific
knowledge which shouldn't exist.
How would you know which is correct?
======================================================
Simple, it has already been hashed/rehashed many times. You are just late to
the party.
Perhaps you could ask your local university to do some research and
find out. Oh, I forgot, that suggestion has been made to you many
times in the past. Why don't you ask them, Keith? Frightened that they
might tell you to run away and stop being silly?
You're wrong. Professor Anatychuk knows more about this stuff than
anybody.
He thinks that Volta's frog's leg experiment was evidence of the fact
that thermoelectric effects at ordinary temperature differences are
large enough to stimulate neurological function in animal tissue, see:
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- although I must admit I have no reason to disagree with him.
Remember there is NO ELECTROLYSIS involved.
And of course it would be silly to suggest that the materials used in
restorative dentistry are exempt from the laws of nature.
Keith P Walsh
PS, Remember also that there is no muscle tissue in the upper or lower
mandibles of the human head, although there are some very sensitive
organs nearby which are linked to the teeth by nerves.
Yes, "thermoelectric".
For an elementary description of the thermoelectric effect go to:
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The general principle is that if you place two dissimilar metals in
contact with each other and establish a temperature difference between
the points of contact then an electrical current will flow, and it
will continue to flow for as long as the temperature difference is
maintained.
And there is NO ELECTROLYSIS involved.
The stageering thing is that for more than a century and a half AFTER
the discovery of the thermoelectric effect, dental students in dental
schools were taught to believe that dissimilar metals in contact with
each other are only able to generate an electrical current if they
become involved in an electrolytic reaction! See:
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This might explain why the dental profession is full of dozy dim-
witted dunces. (I'm referring to the ones who were fooled into
believing that dissimilar metals in contact with each other are only
able to generate an electrical current if they become involved in an
electrolytic reaction.)
Keith P Walsh
What are the "dissimilar metals in contact with each other" in dental
amalgam? Please remember that it is an alloy, not two metals side by
side.
Assuming that in your ignorance you do mean amalgam, please explain
how the different metals in the alloy manage to be at different
temperatures.
Thank you.
That is plain bullshit and proves that during the last years - despite so many
discussions in the net - you did not learn even the slightest thing about dental
amalgam.
Why are you so eager to again and again prove that your are damned stupid!?
.
I read this and had to read the OP article, again. He made his 1st
mistake in Confusing and Amalgam with two separate and distinct metal
pieces.
As in zinc and copper strips in a thermocouple.
The metals are at the same temps and not in separate pieces, how is
any potential generated.
I am curious, too.
Dental amalgam differs from true alloys in its material structure. The
microstructure of the amalgam has a much greater degree of material
inhomogeneity than any true alloy, and this difference is due to the
difference in the ways that the two types of material are formed.
In he case of alloys, ALL of the component metals are raised to a
temperature which is greater than their melting points. After that
they are mixed together thoroughly in their molten state and the
mixture is then allowed to solidify by cooling at a controlled rate.
In the case of amalgams, a liquid metal (mercury for dental amalgams)
is mixed together with bits of solid alloy at a temperature which is
well below the temperature of the solid component(s). When this
mixture hardens what you get is a material which consists of large
(i.e., large in comparison to any variations in the composition of the
microstructure of a true alloy) lumps of the original solid component
which have no mercury in them at all, each surrounded and held
together by a solid matrix of a dissimilar material which does have
mercury in it.
You can see a graphical representation of a typical example of this
"much more inhomogeneous" microstructure at:
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So you should be able to see right there that the amalgam consisists
of "dissimilar metals in contact with each other".
This arrangement of "dissimilar metals metals in contact with each
other" does not look like the fimiliar arrangement of thermocouple
wires which we are perhaps more familiar with and which utilises the
thermoelectric effect to measure temperatures. However it is still an
arrangement of "dissimilar metals in contact with each other", it's
just that the bits of the first dissimilar metal are held within a
solid matrix of the other.
Now, it is an established scientific fact that this type of
inhomogeneous arrangement gives rise to a much more prominent degree
of thermoelectric behavior than in the less inhomogeneous material
structures found in true alloys.
If you go to:
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- you will see a graphical representation of the thermoelectric eddy
current and associated local electromagnetic effect which are
generated whenever a temperature difference applies across a volume of
one electrically conductive material which is completely encased
within another (Fig.d is particularly instructive).
This effect is used to identify the presence of inclusions of
dissimilar materials within material samples by using sensitive
instruments which can detect the electromagnetic effect at the surface
of the sample.
And of course the temperature difference across the inclusion can be
easily induced by applying a temperature difference across the host
sample.
Amalgam dental fillings are subjected to temperature differences all
the time (ever heard of an ice-cream headache?).
And I think you would agree that it would be stupid to suggest that
the materials used in restorative dentistry are exempt from the laws
of nature.
So, my question to you is, do you think that it would be possible to
detect the thermoelectric and/or electromagnetic activity induced in
metal amalgam dental fillings by the application of temperature
differences across them?
Thank you.
Keith P Walsh
PS, dentists sometimes screw metal alloy retaining pins into the root
sockets of their patients' teeth and encase the heads of the pins in
metal amalgam.
I think that even you would have to agree that what you have there is
an example of "dissimilar metals in contact with each other" -
wouldn't you?
Probably not, as mercury and silver are both very good conductors of
heat, so there won't be a lot of little temperature gradients inside a
filling.
Why don't you do the experiment to find out?
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