Dentists who oppose the use of mercury amalgams in restorative dentistry, and in particular those who practise the removal and replacement of amalgam fillings with alternative materials, sometimes face the threat of censure or penalty from their local health authorities and/or dental associations.
If such dentists attempt to defend their position by arguing that amalgam fillings cause harm or illness as a result of the toxic properties of the mercury in amalgams, they are likely to be asked to provide some conclusive scientific evidence for this, and experience indicates that they may be unable to do so.
However, if instead the anti-amalgam dentist simply describes the known electrical behaviors of mixtures of metals, and then asks the relevant authority to explain the extent to which these behaviors occur in amalgam dental restorations, it quickly becomes apparent that the mainstream dental profession is largely ignorant of the electrical behavior of dental amalgams - arguably to the extent of being negligent - and the burden of justification then shifts onto the side of the "pro-amalgam" lobby.
As a prime example of this ignorance, it appears that students in some dental schools are instructed to believe that dissimilar metals in contact with each other are only able to generate an electrical current if there is an electrolyte present and the metals become involved in an electrolytic reaction with it, see;
This is a falsehood.
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 currents 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.
The general principal is that if two dissimilar metals are placed in contact with each other and the points of contact are maintained at different temperatures, then an electrical current flows, and it will continue to flow for as long as the temperature difference is maintained.
For an elementary description of the thermoelectric effect see:
There is no electrolysis involved.
However, in spite of the fact that dental amalgam is an inhomogeneous mixture of dissimilar metals in its own right, and that it is also sometimes placed in direct contact with other metallic objects in the mouth, such as retaining pins screwed into the root sockets of patients' teeth, it appears that experimental investigations to measure the thermoelectric behavior of metal dental restorations have never been carried out (not even by myself).
So, whenever an anti-amalgam dentist claims that amalgam dental fillings may cause neurological disturbances as a result of the electrical behavior of amalgams, regulating bodies such as dental associations are powerless to discredit them for it - simply because it can be demonstrated that those organisations don't know enough about the electrical behaviors of dental amalgams to be able to make any informed scientific judgement on the matter.
Is there any evidence for this?
Well of course there is. Dentist Philip Wander of Manchester in the UK has this to say about the electrical behavior of amalgam fillings:
"Nevertheless, as potentially damaging as mercury in the mouth is the electricity itself. When testing teeth for electrical effects, I have seen momentary sparks of up to one volt - enough to light a small torch or flashlight. It's worth remembering that the currents generated by amalgams are formed very close to the brain, which ordinarily operated at far lower potentials (only a few millivolts). The brain lies only a few millietres from the jaw bone, where the roots of the teeth are inserted, just on the other side of the thin cranial bone and the meninges (the three membranes enveloping the brain and spinal cord). This kind of current can cause mental dysfunction, which I often find in clinical practice."
Not only is Dr Wander able to practise mercury-free dentistry and amalgam removal on health grounds with complete impunity, he appears to do so extremely successfully, counting among his patients some of the world's most famous soccer stars, including none other than the great David Beckham himself.
Check out Dr Wander's website at:
Then there's Dr John Roberts of Huddersfield, also in the UK. Dr Roberts is another dentist who removes amalgam fillings and replaces tham with alternative materials on health grounds. The procedure that he follows when he does this is to remove the fillings in the quadrant of the mouth which has the largest measured electrical potential of any amalgam filling first, followed by those in the quadrant with the next largest electrical potential, and so on. The intended purpose of this procedure is to minimise the effect of any surges in electrical activity caused by sudden changes in the balance between the amalgam potentials as they are being removed.
Dr Roberts appears to have total approval for this practice from the UK General Dental Council's Professional Standards department (see "Amalgam Rmoval Gets .." below).
For a more complete representation of the above arguments, and further references, search Google Groups for the following topics:
"Amalgam Removal Gets UK Approval" "The Prosperity of the Mercury-free Dentist" "Top Dentist Blames Electricity From Amalgams"
And don't be put off by the ridiculing efforts of the pro-amalgam dentists who attempt to dominate these newsgroups - remember that when it comes to the thermoelectric (not to mention electromagnetic!) behavior of dental amalgams, they're just as ignorant as everyone else.
As a matter of fact, I've always suspected that it was the exchange of postings between myself and Joel M Eichen regarding the fate of Dr Anthony G Roeder in "Amalgam Removal Gets UK Approval" that finally convinced Joel to give up his former role as chief ridiculer on behalf of the pro-amalgam lobby at sci.med.dentistry. Old Joel wasn't daft. I think he finally recognised that on the question of the electrical behavior of amalgam dental fillings even he was only able to argue from a position of ignorance - and he decided to get out with his reputation unsavaged while he still could.
My advice for anti-amalgam dentists?
If anyone bothers you just point out that it has been demonstrated experimentally that amalgam dental fillings generate electrical potentials with magnitudes of up to 350 millivolts, see;
The worst you'll get back is ridicule - but remember, that's not because the ridiculers know anything about it. It's because they don't.
Keith P Walsh