In dentistry, we have had to deal with aerosols in the dental office for quite some time. Dentists, their staff and even patients have had to deal with this growing concern. The production of airborne material during a dental procedure is quite apparent to everyone involved. Aerosols in dental hygiene are visible as clouds of various substances vaporize into the air. This pervasive aerosolized cloud is a combination of materials originating from the treatment site and the dental unit waterlines (DUWLs). With the resurgent concern of respiratory infections for dental teams and patients, such as COVID-19, this article aims to take a closer look into what we can do about dental aerosol reduction.
With the COVID-19 pandemic making so many people aware of infectious diseases, it is important to address why this puts dental teams at risk to exposure. COVID-19 can be transmitted in many ways and is an aerosol transmissible disease. When viral particles are aerosolized by a cough, sneeze or dental care, they can potentially travel across great distances, with estimates of up to 20 feet. If there is an infected person, this can then incite secondary infections. These aerosolized droplets can remain in an area, suspended in the air, even after the person who emitted them has left and thus can infect dental workers and contaminate surfaces. Here are some examples of the longevity of COVID-19 in various places:
? The virus can last up to 72 hours after application to plastic and stainless-steel surfaces
? The persistence of the virus can last for up to 24 hours on cardboard surfaces
? The virus is viable up to nine hours on copper surfaces
? The virus remains in suspended aerosols for up to three hours
There is a confusing array of air treatment methods and products becoming available for use in dental offices. Dental clinicians need to decide up front how serious they are about this issue. Currently, there are four common approaches to aerosol control.
1) Physical Clearance
This method involves the intake of contaminated air, treatment to purify that air and release the treated air within the operatory or outside the operatory.
Extraoral suction devices have an extending arm with a hood attached to the end. This hood is positioned near the patient’s oral cavity and is designed to suction debris released during the treatment. A HEPA filter filters it, and the purified air is released back into the operatory.
2) Chemical Treatment
This method involves the release of aerosolized chemicals that disinfect the air in the operatory by killing free microbes and those attached to dust, liquids, small hairs etc. The fogging chemicals decompose into harmless substances such as oxygen and water.
3) Ultraviolet (UV) Light Treatment
UV light with wavelengths between 265-254 nanometers disrupts the nucleic acids of microbes within aerosols, killing them in the process.
4) Various Combinations of Above Methods
All of these approaches can be used within the same device.
All four approaches have advantages and disadvantages and can mitigate potential threats, but none of these approaches used alone will solve all problems.