Pandemics come and go, but aerosols are forever.
It is well documented that aerosols generated in dental practice contain blood, viruses and bacteria that have the potential to transmit disease. Even so, when the COVID-19 pandemic hit, many offices were not well prepared to deal with this threat. The complications associated with droplet contamination, termed spatter, had previously led to the routine use of preprocedural rinses and personal protective equipment. But it was demonstrated that the greatest threat from the SARS-CoV-2 virus comes from aerosols, not spatter.
If these aerosols are not removed, they can linger in the operatory for 30 minutes or more. For many practice owners, dealing with dental aerosols required buying new equipment and making significant office modifications. Concerns from patients and staff, not to mention various agencies and boards, dictated many of these changes. Even so, dealing with aerosols is not a simple task.
The greatest source of dental aerosols is from the use of handpieces and sonic and ultrasonic scalers. Some governmental and nongovernmental agencies suggested the best way to deal with this problem was to eliminate the use of this equipment. While the probability of that happening in the average dental practice is remote, inexpensive devices that attach to a high-volume evacuator have long been available. When placed near the working tip of the instrument, they can reduce aerosols by more than 90%. Air-water syringes and air abrasion devices produce almost as much spray as ultrasonic scalers, but extraoral high-volume evacuators are available that remove the majority of resulting aerosols.
REGARDLESS OF THE APPROACH USED, SOME CONTAMINANTS INEVITABLY ESCAPE
High-speed handpieces also produce contaminants, and that led to the suggestion that rubber dams be routinely used during tooth preparation. This is another unlikely scenario in the average dental practice. To deal with the handpiece challenge, a number of companies have developed evacuation devices in various forms. While any device that reduces spatter and aerosols is highly recommended, regardless of the approach used, some contaminants inevitably escape.
Consequently, an important way to further reduce the threat of disease transmission is to have adequate air circulation in the operatory. Air purifiers are one example, as these devices have been shown to significantly reduce airborne contaminants. An even better solution is to install negative pressure airflow in the operatory. Room air is removed and run through an ultraviolet filtering device or high-efficiency particulate air filter before being delivered outside.
The current variants of COVID-19 will run their course, but the next pandemic is never far away. If it is droplet borne, current methods for dealing with spatter will reduce disease transmission. Recent history would also suggest keeping a supply of N95 respirators and face shields at the ready. Yet taking further steps to address aerosol generation and removal is prudent. In terms of office modifications, these improvements are neither inexpensive nor simple, but addressing aerosols and spatter today will pay dividends if the pandemic flares up — and certainly when the next crisis arrives.
Thomas G. Wilson Jr., DDS
Editor in Chief
twilson@belmontpublications.com
From Decisions in Dentistry. August 2021;7(8)4.
