What's the story with dental work abroad?  When German dentists start advertising their services on Dublin buses, and dental tourists board flights to Hungary and South Africa, it's hard not to think those who stay at home to get their teeth looked after are being done in more ways than one.

It says a lot about prices in Ireland when extensive dental work in South Africa, plus direct flights and seven nights in a top hotel, costs thousands of euro less than having the same work done in Dublin. And how can German dentists offer airport pick-ups in a sports car or a Rolls Royce, a week's accommodation and all the dental work for less than your local dentist?

It's difficult to know for sure as the fees many dentists charge in Ireland remain very much in the shadows.

In a preliminary report into the dental sector published at the end of last year, the Competition Authority found that there was "a very limited amount of accurate information available on private dental fees", other than the stark fact that the price of treatments here has consistently increased faster than inflation. According to the report, while the consumer price index increased by 56 per cent between 1990 and 2004, dental fees increased by 140 per cent.

The report also found that competition among dentists was almost non-existent in the Republic and it described as unsurprising the growth in dental tourism.

"Some consumers have even opted to travel to other countries for certain dental services. This is not surprising when competition is actively discouraged," it said. It made 13 recommendations before starting an extensive consultation process and its final report is not expected until autumn next year.

Dentists overseas have not been slow to take advantage of spiralling costs here. A Munich dental clinic recently ran adverts on buses in Dublin offering all-in packages to Irish "dental tourists". The ads offered patients savings of up to 50 per cent and included collection from the airport in a Porsche or Rolls-Royce as well as hotel accommodation.

This cushy-sounding deal came too late for Rachel Flanagan from Co Kildare. Just over two years ago, she flew to South Africa in search of a cheaper dentist. She wanted to get four veneer crowns, her teeth whitened and a few fillings and was quoted prices of well in excess of €1,000 per crown in the Republic and the same again for the whitening - a lot to pay for work that was essentially cosmetic.

A friend of her father's suggested she get in touch with a Cape Town dentist he knew who did a combination of cosmetic and regular dentistry. She took his advice, took a holiday and saved herself thousands of euro "even when the flights, and the accommodation were taken into account".

Flanagan got the work done for just over €2,000. "The same work in Ireland would have cost me closer to €6,000". She says the dentist who did it was "absolutely brilliant". She was in Cape Town for only a week, a pretty small window in which to get all the work done. Normally, when you're getting a crown, you are required to wear a temporary one for about four weeks while the dentist sends the impression of your tooth to technicians who make the permanent tooth.

"He had the impression taken, the crowns made and fitted within three days and they were absolutely perfect. I have never had an ounce of trouble with them," Flanagan says.

Although it is hard to argue against her experience, the Irish Dental Association (IDA) is always willing to have a go. It accepts that overseas fees seem lower abroad but says that it is important that Irish patients ensure they are getting a like-for-like treatment plan. It has also questioned whether overseas dentists are using the same quality of materials as Irish dentists. The IDA has said if patients examined the deals closely they might find that Irish dentists' prices for such treatments were similar to elsewhere.

As far as Flanagan is concerned, she was definitely comparing like with like. The dentist's surgery she visited in South Africa was, she says, "absolutely gleaming. It was a lot more hygienic than a lot of dental practices I have seen in Ireland.

"Cape Town is renowned as a centre of medical excellence and while there is a lot of poverty in South Africa there is also a huge amount of money. The divide between rich and poor is enormous. But the people in South Africa with the money are not going to spend it on an inferior service. They want the best and they get it."

Her Cape Town dentist, who practised in the UK for several years before returning home, has an excellent reputation, according to Flanagan. "He explains all the processes in great detail so you don't come away with any doubt. And if you're not happy with the work, he will do it again." She is going back to South Africa in February for another crown and to have her teeth whitened again. She says direct flights and accommodation can be easily found for around €1,800. "I know it's a long way away [ the flight time from Dublin is about 12 hours] but there are no problems getting into the country, there's no need for visas or shots and the flights are direct."

A patient who gets certain essential dental work such as crowns done overseas is entitled to the same level of tax relief as they get when the work is done at home as long as the required Med 2 forms are filled out and stamped by the dentist abroad.

Evie Flynn from Dublin had a less positive experience. She was quoted €1,500 for root canal work and a crown at her local dentist, considerably more than the cost in Northern Ireland. She opened the Golden Pages, picked a name at random and travelled across the Border instead. She had the root canal work done for £200 (€300) but developed an infection soon afterwards.

"I have to say when that happened I really regretted travelling. It would have been much better if my dentist was closer then, even though all I needed was a course of antibiotics. I was a bit naive."

This fear that something might go wrong is undoubtedly stopping more people crossing borders. As anyone with bad teeth will readily testify, the last place you want your dentist to be if you wake up at home in the middle of the night in agony is 5,000 miles away. No matter how cheap they are.