Dental surgeries in the UK and Australia say they face a desperate shortage of face masks amid concerns about the coronavirus.
The British Dental Association (BDA) said some larger clinics in the country will run out of masks by the middle of next week and will not be able to treat patients safely under current rules.
A spokesman said more than 50 per cent of face masks used by dentists and other health professionals in the UK are made in China but export of masks from Chinese manufacturers have "essentially ceased".
UK suppliers are therefore restricting the amount that can be ordered, with some suppliers out of stock and others tripling their prices, the spokesman said.
Some dentists and health professionals have also been panic-buying as they anticipate a shortage while the BDA said it had been "bombarded" with calls.
The BDA warned that UK suppliers have issued blanket restrictions limiting dental practices to ordering no more than two boxes of masks per day - 100 masks in total.
The masks are used by dentists and dental nurses, and are also used when sterilising equipment.
Under current guidance, all dental professionals operating in England are told to wear personal protective equipment (PPE) including disposable face masks, clinical gloves, disposable aprons and eye protection.
"In recent weeks dentists have been hit by panic-buying, clumsy rationing and naked profiteering," BDA chairman Mick Armstrong said.
"Unless we see a rapid increase in supply, dentists without face masks will have little choice but to down drills."
The BDA said similar issues are being seen in Australia, New Zealand and Canada.
A message from the Australian Dental Association to the BDA said: "Here in Australia, we are potentially going to be facing a situation of mask shortages as our suppliers all rely heavily on Chinese manufacturers."
It asks what steps can be taken to ensure continued supply and what the BDA is planning to do in the event of masks running out.
Australian Associated Press