Dentists have reached a "tipping point" in recent months over a Government-funded scheme which they say is not fit for purpose.
It comes as more than 260 dentists have left a scheme which provides treatment for medical card holders so far this year.
Thousands of people who had been treated by private dentists participating in the Dental Treatment Services Scheme (DTSS) now face a long wait for treatment.
Fintan Hourihane, Chief Executive of the Irish Dental Association, said many dentists reported that the system is no longer viable from an economic point of view.
He told The Pat Kenny Show: "They all decided in large numbers, those who have left, that they cannot continue, that it's no longer viable for them.
"The scheme has been unfit for practice for many years, it's in place for over 25 years and we have said that it needs to be replaced
"The Department of Health didn't take any great heed of our warnings.
"I think we have reached a tipping point in the last number of months.
"Dentists said, look we are committed to providing care for all our patients, but the system and the scheme that's in place for medical card patients isn't one that's any longer viable from an economic point of view.
However, Mr Hourihane said money was not the only issue for practitioners.
He added: "I wouldn't accept that it is only concerns around fees, because there are restrictions in terms of the treatments that are covered by the state.
"The state doesn't make any provision where a dentist has a treatment plan which includes treatments not covered by the scheme and there's no provision as to how those are to be delivered.
"Dentists are saying for a variety of reasons, partly it's to do with the economics of it but it's not only that, that they can't continue."
Mr Hourihane said that the association has told the Department of Health that the scheme needs to be replaced entirely.
He explained: "We have warned the state that it needs to replace the scheme with something significantly different.
"Which is all about making it affordable for people to visit their dentist and that's something that's urgently needed.
"There are a number of ideas, tax relief, vouchers, that are available for patients to reduce the cost to them.
"Replacing a flawed scheme with a slightly modified flawed scheme isn't the answer.
"We have said to the Department that there needs to be an entirely new approach to making dental care affordable to everyone."
With regard to COVID-19, Mr Hourihane said he did not believe patients were reluctant to visit dental surgeries over fears of contracting the virus.
He said: "There was a backlog because of restrictions in the early stages which mean that care was confined to emergency care
"The full gamut of dental care has been available since mid-May and in fact, there are long waiting lists in many surgeries so there is no evidence that patients are concerned
"Patients were used to seeing significant hygiene and infection prevention control practices long before COVID so that was probably a reassurance for them.
"Dentists have a lot of ventilation systems in place, they have gowns, gloves and masks and there are a lot of enhanced safety standards that have been introduced.
"When you're in the chair, there are significant infection precautions [that were] in place long before COVID."