The health risks faced by dental staff and what can be done

COVID-19 has renewed the interest in aerosols in the dental office. Inhalation of airborne particles and aerosols produced during dental procedures may cause adverse respiratory health effects and bidirectional disease transmission. In the US alone, six million deaths per year are attributed to both chronic and acute respiratory infections and many are linked to oral microbiota and microorganisms. The number of dental procedures that create aerosols has increased and so the risk to dental staff is greater. Dental personnel and patients are exposed to tens of thousands of bacteria per cubic meter, and the potential to breathe infective aerosols is high.

The frequency of close, face-to-face interaction within a dental surgery means the risk of person-to-person transmission, including direct (coughing, sneezing, saliva and other droplet inhalation) and contact (with oral, nasal and eye mucous membranes and contaminated surfaces) is heightened. Microorganisms in the mouth and respiratory tract can be transported in aerosols and spatter generated during dental procedures. The closer the dental staff work to the patient, the higher the transmission risk from a variety of sources.

Within a dental surgery, aerosols can remain in the air for a long time, may be transported for long distances in air flows and can contaminate areas beyond the patient’s immediate vicinity.  Furthermore, risk is present when airborne droplets settle on surfaces. SARS-CoV-2 (the viral cause of COVID-19) can survive anywhere from four to 72 hours on hard surfaces. There is also evidence that some microorganisms live within splash or spatter and even when the surface dries, they may become airborne as dust particles.

Indeed, current guidelines in England suggest dentists must allow an 60-90 minutes between appointments to allow the room to ‘settle’ before they can consult another patient.

Potential transmission routes of COVID-19 in dental clinics[1]


As lockdown measures begin to be lifted and dental surgeries are being given the green light to reopen if they put in place appropriate safety measures, many are struggling to welcome patients back. At the beginning of June, a poll by the British Dental Association (BDA) suggested that one-third of the 2,053 practices in England that were surveyed would open, with 60% anticipating an end of June limited return. Of those who have started to return, the majority anticipate only offering basic or emergency treatment for many months to come. Even when they are working, stopping the spread of the virus, or indeed any contamination, will have a huge impact on how the surgery operates day-to-day. Many aren’t ready with the equipment they need. There have been numerous reports of patients attempting to carry out their own treatment while dentists struggle to cater for those who are in pain and those who have already paid up front and were mid-way through treatment when lockdown was enforced.

What’s the solution?

With the dental waiting list growing by a reported 40,000 a day in the UK alone, decisive action is required to get dentist surgeries back up and running, instilling confidence in their patients and protecting themselves.

Guidance differs from country to country but in general, dentists will need to demonstrate they have adequate infection prevention control (IPC) and source personal protective equipment (PPE). There are a number of infection control measures that can be implemented to block person-to-person routes of transmission and should be implemented at room, local and direct level.


While face masks are a very useful tool and may be quick to get hold of, they do have their limitations, especially when considering the size of COVID-19 particles (approximately 0.125 microns). N95 filters, like face masks, filter most airborne particles down to 0.3 microns.

Read more about the benefits and limitations of face masks and extraction


Good ventilation can have a very definite positive impact on the spread of infection, reducing the amount of aerosol transmitted during dental procedures. Having extraction in place direct at the patient’s mouth gives the best chance of capturing the contaminate at source.

Where it goes next is crucial. HEPA and carbon filters are essential in improving air quality. They send air through various pre-filters to assist with catching airborne particulate, capturing 99.997% at 0.3 microns. Although the COVID-19 particles are smaller than this, they get captured by diffusion, meaning HEPA filters are extremely effective at capturing nanoparticles, even smaller than COVID-19.

Enhancing technology to protect staff and patients and run a clean facility

Extraction systems such as BOFA’s DentalPRO Aerosol helps to reduce risk of cross contamination between dental staff and the patient during examination.

With a market leading airflow to ensure optimum capture, it is designed to work alongside appropriate PPE guidelines. The DentalPRO Aerosol works by extracting contaminated air away from dental staff breathing zones and passing through a series of filters.

It is simple to use and maintain, and there’s no need to vent outside as the filtered air is sent back into the room. Its three-stage filtration includes a HEPA filter which removes 99.997% of particles at 0.3 microns.

Due to the large adjustable flow rate, the DentalPRO Aerosol may be used for a variety of procedures between dental staff and patient and can be turned to maximum capacity for applications that involve heavier aerosol generation.

With a sleek design, this is an ideal addition to any dental setting, offering maximum protection and minimal interference. Download our DentalPRO Aerosol datasheet for more information or contact us.


[1] Peng X, Xu X, Li Y, Cheng L, Zhou X, Ren B. Transmission routes of 2019-nCoV and controls in dental practice. Int J Oral Sci. 2020;12(1):9. Published 2020 Mar 3. doi:10.1038/s41368-020-0075-9.