The Blue Door Dental Practice has written to inform 5044 adults that they will be deregistered as NHS patients from March.
Of the five dentists who will be providing services at the Castle Street surgery as of next year, three have chosen to move into a private monthly dental plan for adults aged 18 years and above.
Only two dentists will continue to provide services under NHS dental contract.
However, all under 18s will remain registered as patients at Blue Door and continue to be offered NHS dental care, including those who are registered with the three associates who are moving to a private business plan.
NHS Dumfries and Galloway have advised those patients losing their registration to seek alternative provision.
But they warned there are, at present, no dentists within the region accepting new NHS registrations, meaning that the alternatives are to secure registration outwith the region or access dental care privately.
Director of public health Valerie White yesterday said: “The situation regarding access to NHS dental services in Dumfries and Galloway is a significant concern and one the Board is taking very seriously.
“We continue work to encourage and support dentists to provide NHS general dental services and are working closely with Scottish Government colleagues on these matters.
“However, lack of dentists coming to work in the region is a key issue, and challenges in dental workforce is being seen across the UK.”
Meanwhile, South Scotland MSP Colin Smyth said the very existence of NHS dentistry in Dumfries and Galloway is ‘under threat’.
Describing the latest move as a ‘massive blow’, he added: “It just seems to be one dental practise after another axing or reducing NHS services and the Scottish Government are like rabbits caught in the headlights. They have no ideas or plans to deal with this crisis. As a result the very future of NHS dentistry in Dumfries and Galloway is under threat.
“Patients in Dumfries will have to join many others across the region in either having to pay for private care or try to find another dentist that provides NHS care but that is almost impossible locally. It is effectively the privatisation of NHS care in Dumfries and Galloway.
“Unless both governments face up to this crisis in our area, it is only a matter of time before no adult in our region will have NHS dental care.”