By David Fenton and David Fuller
When Mary Stephenson began suffering depression shortly after giving birth to her first child, it was the start of four decades of mental anguish.
Mary had her fillings replaced with plastic over two months
Every anti-depressant and therapy was tried, with no effect, and her condition became steadily worse.
When she began to harm herself two years ago she was sectioned under the Mental Health Act and taken into a secure unit.
Doctors were baffled by her condition, labelling her "a conundrum".
It was a chance remark by a family friend that finally led to an unusual course of treatment, and the one which Mary believes has cured her.
Her family from Lymington in Hampshire are convinced she was suffering mercury poisoning from the fillings in her teeth.
But the Department of Health says billions of such fillings have been used worldwide.
"The DoH has no evidence to suggest that mercury-based dental fillings pose a serious hazard to health," said Chief Dental Officer Prof Raman Bedi.
'Ups and downs'
Like many women, Mary's first pregnancy led to calcium deficiency and she needed 19 mercury amalgam fillings.
Shortly after her son was born she entered a spiral of depression.
"I put it down to what was happening in my life with the ups and downs I was having that I would feel a little depressed," she said.
"There were times that I really wanted to end it all because life was so awful and hopeless."
Her husband John said she gradually changed into a different person, one he did not recognise.
"She couldn't relate to young people and didn't really want them around her," he said.
"It was very hard because it wasn't her as I knew her."
After hearing about mercury poisoning, the family persuaded the hospital to allow her to visit a dentist in January 2004.
Over three months he removed the mercury fillings and replaced them with plastic composite.
At the same time she began a course of detoxification, taking 45 tablets a day to remove all the mercury from her body.
At first nothing happened, but then she started to get better.
Mary's husband John said she "turned into a different person"
By August she was able to leave the hospital for shopping trips and she was formally discharged back home on 21 October.
"The day I got out of the unit we went to the theatre," she said.
"In the interval I went to the toilet and as I was walking up and down the stairs I thought - I'm a free person - and that was lovely."
Mercury fillings have already been banned elsewhere in Europe, and the UK government advises that they should not be given to pregnant women as a precaution.
But they add that there have been billions of such fillings fitted and there is no evidence to show that they are a hazard to health.
A British Dental Association spokeswoman said only a tiny number of people have proved to be allergic to mercury and that a mercury sensitivity test could be requested from GPs.
The head of the Hampshire NHS trust treating Mary, Martin Barkley, said they were keeping an open mind over the case.
"We agreed to her family's suggestion that she took mercury detoxification tablets. It is true that over a period of time her illness remitted," he said.
"The consultant psychiatrist has done a presentation of this case at one of the Trust's medical staff teaching forums in which he said that we need to open minded about this possibility."
My dad had mercury amalgam fillings and had them all removed because he believed they were making him ill. He was a physicist with a strong interest in chemistry and he taught me about eight years ago that mercury was potentially a nerve poison. He had an IQ of over 180, but after he had mercury fillings he felt like he had "lost his edge". He died in 2002, but advised me never to get mercury fillings. I have seven fillings - all of which are plastic composite - and I feel fine! I'd never risk putting mercury into my mouth.
Rachel Griffiths, Reading, Berks
I have never had a problem as such. But then again if doctors don't see mercury fillings as a problem how is the ordinary lay person. But then again, what do dentists have in their teeth? I bet they don't put mercury in their teeth.
If there is a risk and let's face it, we know mercury is a poison, then it should be banned, just the same as other countries.
Scott Wallace, UK
I have met people who believe that mercury amalgam fillings can cause a particular type of cystitis (non-infection). This type cannot be treated with antibiotics and causes pain, embarrassing incontinence and stress for many years. Apparently, mercury poisoning can be detected in the eyes, which is how one lady found out she has mercury amalgam poisoning and when treated her cystitis also disappeared. At the end of the day, whether it is the cause or not, mercury in the system surely cannot be good for one's health. I would urge anyone with 'conundrum' symptoms and mercury amalgam fillings to have them removed and take a course of detoxification.
C Leebs, Milton Keynes, UK
Naturally one hopes that Mary Stephenson's nightmare is over, and that her spells of depression have gone for good. But what if they have not? Suppose they were to return, in a year, or five years, or 10? Would we be told of her sad relapse, or be left in ignorance, while still harbouring unjustified fears about the safety of our own mercury fillings. Removal of fillings is no panacea, we are told, since the very act of drilling them out can release far more mercury than leaving them where they are. It is far easier to create a scare, one that leaves folk sick with worry, than to lay these ghosts to rest.
Colin B, Antibes, France
There is a very high placebo effect in any sort of surgery.
I have seen lots of people who felt better after knee arthroscopy, which has subsequently shown to be worthless.
Sarah Francis, brighton, uk
Quote "A British Dental Association spokeswoman said only a tiny number of people have proved to be allergic to mercury ".
This shows the complete lack of awareness on the part of the BDA. Mercury is a very powerful poison and to say that someone is allergic to it implies that the substance they put in your mouth is inherently harmless. This is not true. You don't have an allergic reaction to a poison.... it poisons you.
Secondly, if the BDA say there's no evidence of any danger then why are mercury amalgams not allowed to be used for people under 16 or who are pregnant. Surely, if it's not safe for under 16s then it shouldn't be used for adults either.
Jake Lewis, London, UK.
Having had many mercury fillings in the UK without worrying about it, when I had emergency dental treatment abroad the dentist was horrified to see mercury fillings in my mouth. He then offered for his personal professional pride to replace them all for me at cost price, which he did the next time I went. I now get all my dental exams done on holidays, and will have my children's teeth cared for abroad too.
Perhaps if she'd looked after her teeth properly she wouldn't have needed fillings. I cannot abide this society of blame - it is her fault and no-one else's.
There is no evidence that this recovery was caused by the mercury in fillings. Statistical evidence from the millions of people who have had mercury fillings suggests that even if this was the cause of Mary Stephenson's psychiatric problems then she is a very rare case. Yet your programme will have made thousands of viewers worry about their fillings, and led many to believe that they are in danger and should even consider the painful, costly and completely unnecessary replacement of perfectly safe fillings.
Richard Ellis, Micheldever, Hants, UK
Mercury, being one of the worst organic poisons on Earth, affects people in different ways, depending on their genetic makeup. Where they have a weakness, it takes effect. It may be MS, Parkinson's, depression, schizophrenia, often something neurologically associated. Some folks seem to be immune, but who knows what part of their health might have been better without the toxin in their systems.
Skip, Ardmore, OK, USA
I worked as a dental nurse years ago for just under 10 years,before amalgam was in capsules, thus mixed mercury and alloy by hand using pestle and mortar and squeezed excess mercury out through gauze. I have a mouth full of amalgam fillings. Recent poor health has led me to seek private specialists as the NHS has only treated my symptoms as they arise. I have had chronic fatigue to the point of giving up work, metallic taste , dizzyness, blood pressure problems etc. and when queried mercury as possible factor to the NHS hospital, they will not even entertain idea. Privately I am now dettoxing and considering removal of amalgams with a mercury-free dentist, but at my own expense. Why is subject so taboo to the medical profession! surely science should always question. Why are so many people seeking alternative/complimentary medicine. It may be because orthodox medicine doesn't always have the answers and evidence is only based on certain scientific tests-if a person's illness cannot be proved by scientific test-does it mean that they are not ill?