Australian health authorities fear that about 11,000 dental patients may have been exposed to HIV and hepatitis due to poor equipment sterilization and infection control at clinics in Sydney.
New South Wales Health said 12 dentists from four surgeries were accused of poor cleaning and equipment sterilization practices and advised patients to get blood tests for HIV as well as Hepatitis A, B and C as a precaution.
While NSW Health director of health protection Jeremy McAnulty said no cases had been found so far and the risk of transmission was low, there was concern about people who had undergone invasive procedures.
"It's important to stress we have no evidence of infection at this point, that no transmission has occurred," he said. "But the experts have been concerned in light of the reports of the problems with infection control at these facilities, that a risk is there. We are hopeful there won't be transmissions and the risk is thought to be low but it's best for people to know their status because there are treatments available for infections."
The worry is that instruments may not have been properly cleaned and sterilized, risking the transmission of blood-borne diseases into the gums.
The scare was sparked by a complaint about one of the practices in November last year and subsequent investigations revealed "significant" safety breaches at the clinic and others, said Shane Fryer of the Dental Council of NSW.
"Audits showed that there were some problems with the cleaning, sterilization and storage of instruments in that it was not being done in compliance with the guidelines of the dental board of Australia," he said.
"I want to assure the public that there are stringent guidelines in place in relation to infection control, that dental practitioners must adhere to."
"Failure to do so will result in disciplinary action and possible de-registration."
So far six dentists have been suspended and another six have had conditions placed on their licenses.
One of those suspended, Robert Starkenburg, admitted to the Sydney Daily Telegraph he had been "behind the times" but said he had adopted new protocols since being investigated.
"I don't infect my patients but I didn't have a spick and span office like the new guys," said the 75-year-old. "But I'm spikko now."
He also accused NSW Health of holding a "kangaroo court" against him, the Telegraph reported.