Front Line Innovations – Aerosol Management Part 2

Research has shown COVID-19 is transmitted through aerosols. To combat this the CDC recommends aerosol management practices for dental offices. In part two of a three-part blog series Dr. McAllister Castelaz, the dental director at Horizon Health Services Ivor Dental Center shares how aerosol management is reshaping dental care. View part one of the series here

In part one of the aerosol blog series, I shared how dentists should be prepared to address any concerns patients may have about aerosols. In this second blog, I look at how we as clinicians can use the latest research and guidelines to implement aerosol management practices.

Why dentists are making changes to limit aerosols

Before the COVID-19 pandemic, my choice of suction was dependent on the procedure I was performing and aerosol production was not my first thought. Now, with new CDC recommendations and efforts to provide dental care in the safest possible environment, we are re-examining our practices.

Screenshot from ADA webinar “The Role of Aerosol on the Transmission of Coronavirus and the Impact in Dentistry.

The ADA webinar: “The Role of Aerosol on the Transmission of Coronavirus and the Impact in Dentistry” shows why dentists are taking aerosols seriously. Petri dishes were placed at various locations along the patient, dentist, and dental assistant as well as in different locations of the dental operatory.

Five different procedures were performed, and the study found that with any of the procedures the petri dish placed on the patient’s chest consistently grew significantly more colonies than other petri dishes.

Screenshot from ADA webinar “The Role of Aerosol on the Transmission of Coronavirus and the Impact in Dentistry.

Additionally, depending on the area that where work occurred, the dentist or the dental assistant’s petri dishes demonstrated more growth of colonies. The growths represent the ability of bacteria, viruses, and other aerosols to travel beyond the patient's mouth and survive on other surfaces, spreading beyond the mouth. Steps to help eliminate potential sources of transmission and possible infection are more important than ever.

The ways dentists are addressing aerosols

Dentistry is a field well in-tuned with infection control and engineering measures, many of the CDC interim COVID-19 recommendations for dental settings take advantage of familiar engineering controls. For example, in the past, we’ve used high volume evacuation (HVE), which is a type of suction that draws in a large volume of air over a short period of time, during a filling appointment. As I prepare a tooth with my high-speed handpiece (drill) that sprays water, my assistant holds the HVE suction next to the area where I am working to capture all the splatter and aerosols generated as a result. Before COVID-19, sometimes we would opt to use a different type of suction more for the patient’s comfort. Occasionally, I would perform dental work without an assistant and maneuver the suction and my handpiece as I did in dental school. However, the HVE is now the standard suction used and I am always assisted during an aerosol-generating procedure.

Rubber dam placement example. Image sourced from Google Images.

In addition to increased utilization of an HVE suction and always assisted aerosol-generating procedures, dentists are more frequently placing rubber dams when performing restorative appointments. A rubber dam is a stretchy material that is placed over a patient’s mouth to aid in the isolation of a single tooth or multiple teeth in the area where a dentist is working. The rubber dam creates a barrier between the patient’s mouth and outside environment and improves isolation of the dentist’s working field. There are many styles and techniques of rubber dam placement, but here is a general tutorial. The rubber dam not only creates a barrier between the patient’s mouth and environment, but it can also aid in minimizing the spread of aerosols during a dental procedure. Not all dental procedures are suited for rubber dams, nor are all patients able to tolerate rubber dams, however, they can provide a valuable addition to aerosol management.

A few weeks ago, the CDC removed its recommendation for wait time between cleaning and disinfection of rooms for patients who are not suspected to be COVID-19 positive. Initially, the CDC recommending the wait time to allow aerosols to settle on surfaces, then these surfaces could be wiped and disinfected effectively using FDA approved products. However, there was little evidence to support this need to settle and that following infection control protocols with FDA approved cleaning and disinfectants was appropriate. Instead, greater emphasis was placed on optimal ventilation in the dental offices.

Both the CDC and OSHA have emphasized the importance of well-maintained ventilation systems during this time as well. In my clinic before opening again, we consulted with an HVAC professional and updated our HVAC system to the best of our ability to his recommendations to align with CDC and OSHA guidelines.

Along with well-maintained HVAC systems, the CDC’s updated guidance also suggests the placement of a portable HEPA filtration device. HEPA, which stands for high-efficiency particulate air, is a device that forces air through a mesh filter that catches pollen, dust, and other particulates in the air. While I am aware of dental colleagues who utilized these devices before the COVID-19 pandemic and others who have installed them since the pandemic, it is important to understand there is still little independent research that demonstrates the efficacy of these devices.

My clinical techniques will change as well as the appearance of our dental offices, but the goal will remain the same, to provide safe, effective dental care. Sharing information with patients on the changes we’re making and why will build confidence that going to see the dentist is safe. In the next and final part of our aerosol series, I’ll share how minimally invasive techniques can be added to reduce aerosols and improve overall health.