Barriers are most effective aerosol mitigation strategy in dental clinics: Study

A dental aerosol is an aerosol that is produced from dental instruments, dental handpieces, three-way syringes, and other high-speed instruments. These aerosols may remain suspended in the clinical environment. Dental aerosols can pose risks to the clinician, staff, and other patients. The heavier particles (e.g., >50 µm ) contained within the aerosols are likely to remain suspended in the air for a relatively short period and settle quickly onto surfaces, however, the lighter particles may remain suspended for longer periods and may travel some distance from the source. Aerosols are generated routinely during patient care in dentistry. Managing exposure risk requires understanding characteristics of aerosols created during procedures such as those performed using high-speed drills that operate at 200,000 revolutions per minute.

With thorough preoperative planning and the use of this investigation's findings of the effectiveness of mitigation strategies as a guide, dental offices may be able to return to prepandemic productivity.

A trained dentist performed drilling procedures on a manikin's incisors (teeth nos. 8 and 9) using a high-speed drill and high-volume evacuator. The authors used high-speed imaging to visualize the formation and transport of aerosol clouds and particle sampling to measure aerosol concentration and size distribution at several locations. The authors studied several aerosol mitigation strategies.

The Results of the study are:

Aerosols produced during high-speed drilling were erratic and yielded high concentrations that were at least an order of magnitude above baseline. High-speed imaging showed aerosols initially travelled at 1 m per second. Owing to the erratic behaviour of aerosols, supplemental suction was not effective at collecting all aerosols; however, barriers were effective.

Thus, the researchers concluded that the barriers are the most effective mitigation strategy. Other methods studied have limitations and risks. To the authors' knowledge, this article presents the first characterization of aerosols generated during high-speed drilling by a dentist.

Reference:

Experimental evaluation of aerosol mitigation strategies in large open-plan dental clinics by Min Zhu et al. published in the Journal of the American Dental Association.

https://www.sciencedirect.com/science/article/abs/pii/S0002817721005432