“Getting your teeth cleaned does not increase your risk for COVID-19 infection any more than drinking a glass of water from the dentist’s office does,” said lead author Purnima Kumar, professor of periodontology at Ohio State.
“These findings should help us open up our practices, make ourselves feel safe about our environment and, for patients, get their oral and dental problems treated — there is so much evidence emerging that if you have poor oral health, you are more susceptible to COVID,” Kumar said.
SARS-CoV-2 spreads mainly through respiratory droplets, and dental procedures are known to produce an abundance of aerosols — leading to fears that flying saliva during a cleaning or a restorative procedure could make the dentist’s chair a high-transmission location, the university wrote in a press release.
The researchers wanted to determine whether saliva is the main source of the spray, so they collected samples from dental office employees, equipment and other surfaces reached by aerosols during a range of dental procedures.
By analyzing the genetic makeup of organisms detected in those samples, the researchers determined the water from irrigation tools, not saliva, was the main source of any bacteria or viruses present in the “spatter and spurts from patients’ mouths,” the university wrote. “Even when low levels of the SARS-CoV-2 virus were detected in the saliva of asymptomatic patients, the aerosols generated during their procedures showed no signs of the coronavirus. In essence, from a microbial standpoint, the contents of the spray mirrored what was in the office environment.”
For their study, the researchers enlisted 28 patients receiving dental implants and restorations using high-speed drills or ultrasonic scaling procedures in Ohio State’s College of Dentistry between May 4 and July 10, 2020. The scientists collected samples of saliva and irrigant (the water-based cleaning solutions used to flush out the mouth) before each procedure and, 30 minutes after, aerosol remnants — condensate — from providers’ face shields, the patient’s bib and an area 6 feet away from the chair.
No matter the procedure or where the condensate landed, microbes from irrigants contributed to about 78% of the organisms in aerosols, the researchers found. On the other hand, saliva, if present, accounted for 0.1% to 1.2% of the microbes distributed around the room.
Despite their findings, Kumar added, “we should not lose sight of the fact that this virus spreads through aerosol, and speaking, coughing or sneezing in the dental office can still carry a high risk of disease transmission.”