Health care professionals are trying to navigate the new coronavirus pandemic from a safety and economic perspective. But while many can work from home or continue with social distancing, dentists do not have that opportunity — and will remain “high risk” for potential exposure to COVID-19 due to proximity to patients and the aerosols produced by some procedures.

Steps need to be taken to ensure the safety of our staff, patients and communities. The key is understanding the options for dental practices to help mitigate viral spread.

In my opinion, testing must be at the forefront. We need to be able to test our staff and patients with rapid results. Treating a coronavirus-positive patient must be avoided at all costs until there is an available vaccine or effective treatments. With the high prevalence of asymptomatic carriers, the only way we can be sure it is safe to treat patients is if we can test.

As researchers continue to discover more about the disease process, understanding if patients have antibodies will be crucial. Dental providers have to push for testing capabilities since we are on the front lines to safely treat and protect against new community spread.

PRACTICE RECOVERY: Spear Online members can begin Practice Recovery now and discover the “4 Key Initiatives” for break-even strategies to mitigate the financial strain and align your team to treat patients in this unprecedented time.

Many dentists are preparing to reopen their offices. Our priority will be to do so in the safest manner possible. In this article, I highlight a few options that can potentially limit exposure. Being fully informed will help determine the most appropriate options for your office and make your purchasing decisions easier.

Pre-appointment systems: Questionnaires, digital temporal thermometers and pulse oximetry

Pre-treatment health questionnaires help in understanding risk and potential for exposure. Digital temporal thermometers work well and are very accurate. My office will be testing staff first thing in the morning and at noon.

Pulse oximeters can be used to determine if a patients oxygenation levels are unknowingly depressed, at less than 90%, which can be an early sign of hypoxia — a common sequela of the disease. Documentation is important to understand an individual’s baseline temperature and oxygen saturation, so we can better determine the potential for symptomatic disease and monitor any deviations.

Patients should also be screened when they enter the office. Asking patients to call the office upon arrival is important to mitigate an increase in office traffic. Our office system is set up to notify the patient on their cell phone when the treatment room is ready for the patient, so they can be ushered directly into the operatory and minimize communal interaction.

Personal Protective Equipment (PPE)

With the number of doctors and nurses that have contracted COVID-19, dental professionals should probably look at this as a “barrier.” Medical gowns, gloves, Level 3 masks and N-95 masks (when there are aerosols) are critical and obviously recommended. Adding face shields and head coverings will also help limit exposure.

The issue many dentists face is the current lack of supply. For many offices, it will be unsafe to treat patients until they can restock offices and staff can be properly outfitted. Last, I checked there was a three-week back order on gowns alone, not to mention ordering limitations on surgical and N-95 masks.

High Volume Evacuator (HVE)

Aerosols must now be considered in patient treatment. The new coronavirus particle size is 0.1 microns, which is why it is so debilitating. It is small enough to get into the alveoli of a patient’s lungs, thus is more difficult to eliminate.

Options to help decrease aerosols include rubber dams or products like Isolite, combining them with High Volume Evacuator (HVE). A recent study in the Journal of the American Dental Association demonstrated a significant decrease in aerosol and spatter with Isolite compare to HVE and HVE combined with rubber dam. Cavitrons create a significant amount of aerosol and most hygienists do not have a dedicated assistant to evacuate and reduce spatter.

Considerations must be taken to help protect your team and the patient. Products like Dentsply Sirona Purevac HVE would seem to be more beneficial than many of the units that primarily use slow-speed evacuation.

Extraoral suction units

While extraoral suction units have really caught many dentists’ attention lately, there are many features that must be understood. The first are filters.

A HEPA filter can only filter particles down to 0.3 microns and COVID-19 is 0.1 microns. The theory is HEPA filters still provide some defensive filtration as impacted by the water and the viral load. But there is a wide range of HEPA filter grades. You must investigate the classification of the filter to determine its efficacy.

An ULPA filter is graded at 99.7% for particles 0.1 microns in size. This is the filter that would appear most ideal. However, many extra oral suction units do not come supplied with this filter. So, the question dentists must ask is if these units are not using an ULPA filter, are these units effective, safe and worth the investment?

More research must be done. Understanding a unit’s “capture rate” (its power to capture as much of the aerosol as fast as possible) is also critical. The more powerful the unit, the better the capture rate, thus decreasing escape of viral particles.

The combination of filters and capture rate needs to be fully understood before equipment is purchased. It’s important to not allow yourself, as a consumer, to be driven by fear. Spending thousands of dollars only to find out these units are ineffective could seriously affect an independent dental practice during this terrible public health and economic crisis.

UV lights to disinfect aerosol particles have the chance to leak ozone into the air. UV lights need to be properly sealed and I read one report that the seal can be compromised easily on the external suction units. The two most prominent companies supplying external suction devices are ADS and Sentryair, which is offering Spear dentists a 10% discount (use promo code “speardentalpromo2020”).

I would highly recommend you research the differences between the two units.

Room air purifiers

Room air purifiers can also be considered to help capture viral particles. Again, consumers must understand the questions to ask prior to purchase.

Rate of air change per hour is the guiding principle for these units. A formula of Cubic Feet Per Minute (CFM) multiplied by 60 minutes is used to determine the most effective unit based on the volume of the room. This provides a guide to the number of times the air changes per hour.

The U.S. Food and Drug Administration recommends maintaining a minimum of 20 air changes per hour for a clean room. The Centers for Disease Control and Prevention requires operating/surgical rooms to have a minimum of 15 air changes per hour.

The power of the unit measured in CFM is critical in air rate change, as well as the type of filter.

Filters, particle size and other virus-related considerations

Consumers will have to consider filters and particle size. Currently with this virus size, it would seem the ULPA filters would be most ideal. UV lights to help disinfect particles are also recommend for air purifiers and are offered on many units.

Our patients will demand to know what actions our offices are taking to protect them and our team from COVID-19. The optics will matter and the measures we take now will reflect our commitment to optimal health for all those we care about.

Information is key and unfortunately there are many unknowns and lives are at risk. Until there is a vaccine, providers need to determine what is the best way we can protect the community, not only against COVID-19, but for future viruses too.


1) Evaluation of the spatter-reduction effectiveness of two dry-field isolation techniques. JADA 2012 Nov; 143 (11) 1199-1204

2) Regulatory education for industry (REdI): Facilities & Equipment: CGMP requirements July 16 2015

3) CDC Appendix B. Air Guidelines for environmental infection control in health-care facilities (2003)


Commenter's Profile Image Ricardo M.
May 6th, 2020
Nice article Andy !
Commenter's Profile Image Andrew C.
May 6th, 2020
Thank you Ricardo. Hope it helps our community understand some of the options out there.
Commenter's Profile Image Ute C.
May 6th, 2020
Well summarized ! Thanks !
Commenter's Profile Image Jerrold D.
May 6th, 2020
Andy that’s an awesome summary!!! Many thanks
Commenter's Profile Image David B.
May 6th, 2020
Thank you! I see you mentioned the ADS system. I was interested in it but was curious what your opinion was. Thanks again!
Commenter's Profile Image Josh R.
May 7th, 2020
Good work Andy! I too have been skeptical of extra oral suction units. All lit i have reviewed does not talk about the filters in enough detail. I have had ULPA room filters in every op for years now. My brand of choice is Blueair. My motivation was not breathing in aluminum oxide particles. No one knows if the will catch COVID, but they sure sure do help my allergies and far less clean up when I sand blast.
Commenter's Profile Image Josh R.
May 7th, 2020
Just read that the virus needs to be in a droplet of at least 1 micron. So technically most HEPA filters would work. I would still feel better with something that filters down to .1 microns to be safe.
Commenter's Profile Image Julian D.
May 8th, 2020
Thank you for sharing this Andy! Quick question, What are your thoughts on the UV-C light wands for sterilization/disinfection of surfaces?
Commenter's Profile Image Brian S.
May 23rd, 2020
Great summary Andy! One of my concerns with extra-oral suction units would be decontamination. We can't flush the lines like we do with our HVE, how would one effectively clean that big tube that leads to the filter and main unit? Especially considering many have joints and bends. Keep up the good work!