DENTISTS across the Lothians have struck off nearly 18,000 NHS patients in just five years, it was revealed today.
Patients are often "withdrawn" because a dentist has decided to switch to the private sector.
People who fail to pay their dental fees or are verbally or physically abusive to a dentist can also be refused services.
The figures were revealed following a parliamentary question from the Liberal Democrats.
Edinburgh South MSP Mike Pringle today urged the Scottish Government to investigate.
He said: "I find it extremely concerning that in a country with one of the worst oral health records, NHS Lothian approved 'withdrawn' status for 3680 patients between 2006 and 2007.
"I urge the Scottish Government to look into these figures to discover why Lothian dentists have requested so many patients be withdrawn from their lists."
In previous years, a large number of dentists have switched from the NHS to the more lucrative private sector.
A recent study indicated private dentists in the Capital charge £356 for a dental crown, while the same treatment on the NHS costs just £194.
If a dentist chooses to go private, clients are forced to either follow suit or search for a practice accepting NHS patients.
But there are only around 20 practices in the Lothians still registering new NHS patients, and more than half of all adults and over a quarter of children in the region are not registered with an NHS dentist.
It is thought around 19 per cent of these residents pay for private treatment, while the rest go without any care.
Patients are usually "withdrawn" on the request of a dentist, and with the subsequent approval of the NHS board. In the Lothians, figures peaked in 2005-06 at 7357, and fell to 3680 in 2006-07.
Colwyn Jones, NHS Lothian's consultant in dental public health, said: "This trend suggests that access to NHS dentistry is improving across Lothian and demonstrates our commitment to improve and modernise our dental services."
Public Health Minister Shona Robison said that the Government was working hard to encourage dentists to remain with the NHS.
"I welcome the fact that the number of patients who have been withdrawn from an NHS dentist is falling," she said.
"However, I recognise there is more to be done and that is why there are a number of financial recruitment and retention measures are in place to attract dentists to work in the NHS and remain in Scotland.
"We have introduced a dental bursary of £4000 a year for students who commit to working in the NHS and over 400 students have received the bursary in the past year.
"We also provide funding under the Scottish Dental Access Initiative for dentists who wish to establish new practices or extend existing practices.
"This is on top of remote and rural and deprived areas allowances, and dentists who choose to work in the NHS also benefit from significant practice allowances."