The nervy flick through Woman's Realm in the waiting room... the white-knuckle grip on the plastic chair as you are lowered to your fate... the high-pitched scream of the drill. "Please open your mouth," says the dentist. "Just try to relax." Having a filling must rank as one of the most unpleasant experiences of childhood and it doesn't get any better as you get older; in fact, generally the fillings get worse and so does the drilling.

Over the past 30 years, our teeth have got much better. We look after them better, and we're all round more tooth-aware. Many people under 30 can now boast that they've never even had a filling or a crown - something almost unheard of a generation ago. But for those people who don't have the perfect teeth of the fluoride generation and still get cavities, drilling remains a vile and depressing risk every time you go for a check-up.

Now, along comes a new treatment that promises to put an end to this painful collective experience. It's not yet widely available, but has been introduced at a handful of private dental practices across the country. The treatment, called HealOzone, could, according to its cheerleaders, finally banish unsightly fillings once and for all from our mouths.

At first glance, the treatment looks too good to be true. It is, we are told, fast, cheap and almost 100% effective. First, the treatment involves using a laser to detect tooth decay. Then a special airtight rubber cup is attached to the tooth. The air is sucked out of the infected cavity, and replaced with ozone, a powerful germicide. The gas kills the offending bacteria almost immediately, and the cavity in the tooth then either "remineralises" naturally, aided by calcium salts in your saliva, or, if the hole is too big, is filled with a cosmetic white filling (but with no drilling involved).

James Hull Associates, currently the largest chain of dental practices to offer HealOzone, has the required equipment at three out of its 40 practices. Dr Peter Murray, the company's clinical director of dentistry, is bullish after seeing the results. "I see nothing but good coming from it. It works in 90% of cases first time, with the remaining 10% being treated successfully upon second treatment. The treatment takes about 40 seconds per tooth. Beforehand, if you were doing good quality fillings on a back tooth, you were taking at least half an hour with injections and so on."

Advertised as pain-free, HealOzone could actually work out cheaper than conventional fillings. "We've set a rate of £45 a tooth with an initial check-up cost of £65," says Murray. "A conventional white filling costs anywhere between £65 and £95 per tooth." But Murray also believes there needs to be a major change in conventional thinking before it is widely available outside private practices. There's also the small matter of the equipment currently costing £15,000.

But with high-profile industry fans such as Dr Julian Holmes of Wokingham's Adentec Clinic claiming that dentists can reap £576 per hour in profit using HealOzone compared with £108 with traditional fillings, that could act as a spur by dentists to invest.

What could slow things down, however, is initial scepticism about the use of ozone by bodies such as the British Dental Association. "Ozone is a very interesting element," says Gordon Watkins, chairman of its health and science committee. "In the atmosphere it is very beneficial to us, but down at ground level where we breathe the stuff it is known as a pollutant and major cause of smogs and respiratory problems.

"The use of ozone in medical care extends back to before the first world war. It was used to treat gangrene and anal problems. Basically, they would blast it up your back passage. Nowadays, it doesn't have any other application in healthcare in this country. But, interestingly, it is used extensively in Cuba. Apparently, you can't go into a casualty unit in Cuba without being sprayed with ozone beforehand."

While Murray counters that HealOzone is "completely safe because each tooth needs an airtight seal before the ozone is inputted and is so localised that there's no problem", Watkins adds that the US authorities are also sceptical about the medical use of ozone. The federal food and drugs administration is adamant: "Ozone is a toxic gas with no known useful medical application in specific, adjunctive or preventive therapy. In order for ozone to be effective as a germicide, it must be present in a concentration far greater than that which can be safely tolerated by man and animals."

"We would certainly like to see more research done on it," says Watkins, rather diplomatically. "We want assurances that ozone is not harming the mouth." He stresses, however, that the debate over ozone use is largely a side issue when it comes to dentistry. The good news, he says, is that the majority of a dentist's work is now preventative or cosmetic - a marked difference from the fillings, bridge-work and extractions that took up the dentist's day a generation ago.

"The dental condition of the population has improved dramatically over the last 30 years," he says. "We now know the dietary components that cause tooth decay and we know how to strengthen the teeth with the use of fluoride in toothpaste and in our tap water - something that has been taking place since the 1960s. Dental decay is largely a social disease, namely, the culture of high sugar consumption. Dentists are increasingly just treating gum disease - the world's most prevalent disease - and offering hygiene and diet advice.

"The balance is certainly changing. I'm in my 50s and have eight fillings which is actually quite low for my generation. My three children, on the other hand, don't have a filling between them."