THE sight of a hospital ward filled with distressed children has stuck in David Landes' mind over the years. As a young dental officer in the East Midlands in the early 1990s, he had to supervise young children who were being given a general anaesthetic before having rotten teeth extracted.

"A lot of those children were four, five or six years old and pretty frightened. The poor kids had probably been unable to sleep for ages because of toothache and then they were being put through a very unpleasant experience in hospital," recalls Dr Landes, who is now a public health consultant in County Durham.

"But what I really didn't like about this was the fact that, for the vast majority of those children, having extractions was totally unnecessary."

Unsurprisingly, Dr Landes, of Durham Dales Primary Care Trust, shares the view of virtually all public health and dental experts in the UK that water fluoridation could drastically reduce child dental decay within a few years. Adding fluoride to water alters the vulnerable enamel coating of growing teeth, making it much more resistant to decay.

He believes most of the inhabitants of that hospital ward in Leicester would not have been there had local water supplies been fluoridated, because most of the children would have been protected against serious dental decay.

The importance of fluoridated water as a way of protecting children's teeth from decay was highlighted by the chief medical officer, Professor Sir Liam Donaldson, two months ago. In his annual report, Sir Liam pointed to the stark contrast between fluoridated and non-fluoridated areas in the North-East.

In places like Hartlepool, which has had naturally fluoridated water for a century, the average number of decayed, missing and filled teeth in the average five-year-old was 0.86. In neighbouring South West Durham, which is unfluoridated, the average five-year-old has 2.82 missing or decayed teeth.

The conclusion, that fluoridation can dramatically improve dental health in children, is one with which Dr Landes heartily agrees. The public health specialist, who is based in Bishop Auckland, feels particularly strongly about the need to protect children from under-privileged families.

"We have seen a vast improvement in the oral health of this country but parts of the UK, including parts of County Durham, lag behind. They are the unfluoridated areas and the areas with high levels of deprivation," he says.

While he accepts that a minority of people in the UK have strong feelings about fluoridation, Dr Landes sees things in black and white when it comes to protecting children's teeth.

"Within three years of fluoridating our water supplies locally, we would see fantastic improvements in child dental health. We know that fluoridating the water is most beneficial where children have the poorest oral health and, in this area, that is Bishop Auckland, parts of Teesdale, parts of Darlington and areas of Sedgefield."

Specialists working in the NHS have been encouraged by signs that the Government is finally taking a serious interest in fluoridation as a way of reducing background levels of child tooth decay. Legislation is currently going through Parliament which could result in widespread water fluoridation within a couple of years.

The main stumbling block in the past has been the reluctance of the now privatised water companies to get involved in a process which could result in legal action. Changes to legislation is likely to result in the onus being shifted to local strategic health authorities.

It is expected that within the next 18 months to two years, strategic health authorities up and down the country will begin an extensive period of public consultation to assess whether fluoridation is acceptable. If the answer is 'yes', the health authorities would be able to require local water companies to add fluoride to water supplies.

The last time fluoridation was proposed in the region - in 1993 - it encountered strong resistance in North Yorkshire. Proposals by the county's then health authority triggered a public outcry and after a lengthy campaign, the plans were shelved in 1995.

Councillor Richard Hall, a member of North Yorkshire County Council, put forward the successful motion which voted down fluoridation a decade ago. He has no doubt that any new proposals would be fought equally as strongly.

Within County Durham and Tees Valley Strategic Health Authority 80 per cent of the population have unfluoridated water supplies and the only areas currently fluoridated are in Hartlepool, Derwentside and parts of Easington. Further south, the whole of North Yorkshire is fluoride-free while further north, Newcastle and Gateshead have 100 per cent fluoridation.

On the ground, the differences within health authority areas can be quite marked.

"There is no doubt that if you walk into a dental clinic in Consett or Stanley, you will see far fewer kids with holes in their teeth than if you walk into a dentist's in Bishop Auckland," says Dr Landes. "Adding fluoride to water provides the most benefit for people from the most deprived communities where families can't afford to pay £1 for a toothbrush."

But what about opponents, who argue that fluoride can actually damage teeth, producing a mottled effect?

Dr Landes argues that the fact that hundreds of millions of people across the world have fluoridated water supplies and there are no negative health effects is conclusive. As for mottling of teeth, Dr Landes says there are a range of explanations for this condition, including children who have swallowed a lot of fluoridate toothpaste over a period of time.

But Coun Hall promises that the pro-fluoridation lobby "will have a fight on their hands". In the Knaresborough councillor's view, fluoridation is unnecessary because North Yorkshire enjoys relatively good dental health anyway. More importantly, he is against what he calls "mass medication" with a substance which some have classified as a toxic material.

"It is compulsory medication whether you like it or not. That must be wrong. You can only be compulsorily medicated if there is a court order in this country, otherwise it is assault," he argues.

He also believes that patients should be fully consulted and be in agreement before having medical treatment.

Coun Hall says there is evidence that the beneficial effects of fluoride have been exaggerated. "A few years ago there was a report from York University which came to the conclusion that the evidence of fluoride's efficacy was very, very weak," he says.

He is also concerned at the question of matching dosage to weight. "If you are a baby being bottle fed, you are getting more fluoride that you should," he argues.

The York report also suggested that tooth mottling can affect up to 12 per cent of people receiving fluoridated water.

Coun Hall is worried that the rules are being changed to make it easier for fluoridation to be introduced. But he warns the public health lobby should not under-estimate the strength of feeling in the anti-fluoridation camp.

"The manufacturers of fluoride say the chemical should not be put into the biosphere. It is a poison," he says. "If they try to push this through, they will have a fight on their hands."