Aerosols in Ultrasonic Instrumentation: Comparison of particle spread utilizing saliva ejectors versus high-volume evacuation

Abstract

Purpose: The emergence of SARS-CoV-2 has generated renewed interest in the potential transmission of viral contaminants via ultrasonic scaler-generated aerosols. The purpose of this study was to use controlled experimental conditions to quantify the range, direction, and concentration of aerosolized and splatter droplet spread across distances up to 106 inches from the source of the ultrasonic scaling procedure on a manikin patient head.

Methods: A dental simulation unit (DSU) was used to facilitate ultrasonic instrumentation performed on a typodont located within a manikin patient head. A 9 × 9-foot section of white paper was placed on the floor directly beneath the DSU. White paper was also placed on the adjacent countertops for identification of possible spread. Methylene blue dye was mixed with reverse-osmosis (RO) water and placed in the reservoir of the ultrasonic scaler. Experimental tests were run with high-volume evacuation (HVE) and a with a saliva ejector. Photographs of the paper and droplets were taken and analyzed by computer software to identify all droplets captured on the paper.

Results: Particle counts show that HVE use is associated with a reduction in total particle count for each zone evaluated, with the largest reduction seen in regions closest to the origin. Using HVE on the DSU demonstrated a 99% reduction in particles and 50% reduction in the range of particles.

Conclusion: Dental health care providers should use HVE when generating aerosols during ultrasonic instrumentation procedures to reduce particle spread in health care settings.