Dental hygienists in Northern Ireland have said they are frightened and worried about their future.
The society that represents them said its members have experienced reduced hours and struggle to obtain personal protective equipment (PPE).
Hygienists have also had to limit the types of treatment they can offer patients.
The Department of Health (DoH) said it "had to focus available resources on the most pressing problems".
"This has inevitably meant that not all the elements of the dental system have received the attention they would expect during normal times," it added.
Lorna McGrath, the Northern Ireland chair of the British Society of Dental Hygiene and Therapy (BSDHT), said some hygienists have been able to go back to work but things will be very different for patients.
"Before Covid we would have used ultrasonic scalers for polishing teeth or use an airflow, which uses water at a high pressure to remove stains - we can't do these at the moment," she said.
"We have to use hand scaling which takes a lot longer.
"Patients come along expecting pre-Covid treatments but that's just not possible anymore."
Ms McGrath also said that because dentists have to leave an hour between patients, they have cancelled hygiene services so the dentists can use the hygienists' rooms to see patients.
"The majority of dental hygienists are self-employed and work a day a week in multiple practices," she said.
"Many have had their hours reduced or are being asked to work different hours.
"For a lot of dental practices, it just isn't viable to offer a hygiene service at the moment."
'Lack of communication a concern'
Ms McGrath said she was worried about the backlog of patients and the effect it would have on their oral health in the long term.
"Through Covid we've seen an increase in mental health issues and a rise in anxiety and depression.
"In some of these cases we see people lose interest in self-care and oral hygiene is usually one of the first to go."
The British Society of Dental Hygiene said it had tried to open a line of communication with the acting chief dental officer Michael Donaldson so it could raise these issues but it hadn't received a response.
"It's very unfortunate that the acting chief dental officer hasn't responded to our request for a meeting," she said.
"The lack of communication is causing us significant concern."
In response, a Department of Health spokesperson said that "due to the sheer complexity of the issues facing dentistry, and the enormous amount of correspondence being received, the only dental representative organisation DoH has been dealing with is the British Dental Association (BDA)".
"The department recognises the BDA do not represent dental hygienists or therapists.
"If the BSDHT were to outline their current issues in a letter, the department would endeavour to address these and give consideration to a meeting if that was felt to be helpful."