Orange County's health department Friday ordered a troubled Anaheim children's dental clinic to close after its new water system tested positive for bacteria. Children's Dental Group had recently replaced its on-site system after health authorities determined the water had caused infections among dozens of kids who underwent partial root canals there earlier this year.
The Orange County Health Care Agency said it confirmed Thursday that multiple samples taken from the new water system tested positive for mycobacterium, the same culprit in the previous infections.
"This action was necessary in order to determine the actual source of the Mycobacterium since it has reappeared," Orange County Public Health Officer Dr. Eric Handler said in a statement. The county is working with the Centers for Disease Control and Prevention and the Dental Board of California to determine the source of the bacteria.
The department ordered Children's Dental Group to stop using its old on-site water system Sept. 15, and had cleared the facility to use its new system Nov. 8.
There have not been any reports of infections linked to the new water system, according to health agency spokeswoman Rachel Selleck. She added the county is working with the clinic to follow up with families of children who have undergone pulpotomies - partial root canals - since the new water system was installed.
Children's Dental Group CEO Sam Gruenbaum called the county tests "preliminary and unconfirmed," but said "we closed our Anaheim office ... to make sure we are protecting the health of our patients" while officials conduct additional tests.
"Most water everywhere contains some sort of mycobacteria, with only certain species creating any safety concern," he said. "The testing to-date has had inconclusive results and has not revealed a specific reason for concern," Gruenberg said, adding that "we understand and share the desire for caution ... and will take all precautions necessary to ensure [our patients'] wellness."
The clinic will remain closed until it removes all sources of bacteria that pose a risk to patients and the public, the health department said. In addition, the state dental board must certify that the clinic's practices meet its standards and both the CDC and a county-approved independent expert must certify that bacterial levels don't put patients or the public at risk.
The old water system has been linked to 58 confirmed or probable infections, according to the Health Care Agency.
When dentists perform partial root canals, they remove a portion of the pulp, or the connective tissue that contains blood vessels and nerve tissue, according to the American Dental Association. Infections following the procedure can cause swelling, redness and pain around the infected tooth weeks or months afterwards.
Children's Dental Group has offices across the state, but infections have only been linked to the Anaheim location.
The Orange County Health Care Agency has more information about these infections here.
This story has been updated to include Children's Dental Group's response.