Silver & Charlton Dental, based on Atkinson Road in Fulwell, announced via their Facebook page that they were changing to a “fully comprehensive private practice”.
Bosses at the dental surgery have put the move down to a “lack of investment in NHS dentistry and rising costs”.
The Facebook post said: “As valued patients of our practice, providing you with the highest level of dental care is our key priority. For over four decades we have proudly provided that care as part of the NHS.
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“Looking ahead and to ensure your oral health care is our number one priority we have made the decision to move our Fulwell Clinic away from the NHS and into a fully comprehensive private practice.
“From 14th June, Fulwell will offer dental care to adult patients on a private basis only."
Tim Harding is a patient at the Fulwell surgery and he has slammed the way that Silver & Charlton Dental have handled the situation of announcing the change.
He said: “I’m not concerned for myself but I’m concerned for people like the elderly or vulnerable who cannot afford to pay for private dental treatment.
"The practice has only given patients three weeks notice about this change and no thought has been given to the fact that there is no other local dentists available, there are no alternatives.
"Most NHS dentists either have no spaces available for there is a long waiting list to be accepted.
"I get that businesses need to make money however the way that this has been handled via social media is just a disgrace, it is shameful and even more so when austerity is on the rise.”
Silver & Charlton Dental also has another practice, located on John Street in Sunderland city centre, and that is set to remain as a NHS dentist. However, patients at the Fulwell site cannot transfer due to it being at full capacity.
Commenting on their own Facebook post, Silver & Charlton Dental stated: "Unfortunately, you cannot transfer to John street at as they do not have capacity to accept any more NHS patients.
“If you do not wish to join the plan, you will need to find a new NHS dentist.”
The company has also confirmed via their Facebook comments that “patients requiring disabled access, if have been treated within the practice in the past four years will still access NHS treatment at Fulwell, but please be aware it may not be with your usual dentist.”
The Echo has tried to contact Silver & Charlton Dental for comment on the matter but without any success so far.