Sources of SARS-CoV-2 and Other Microorganisms in Dental Aerosols

Ultrasonic scaling in COVID-era dentistry: A quantitative assessment of aerosol spread during simulated and clinical ultrasonic scaling procedures

Objective

Healthcare agencies recommend limited use of aerosol‐generating procedures to mitigate disease (COVID‐19) transmission. However, total dispersion patterns of aerosols, particularly respirable droplets, via dental ultrasonic units is unclear. The purpose of this study was to characterize and map total spatter, droplet and aerosol dispersion during ultrasonic scaling in simulated and clinical contexts.

Methods

Ultrasonic scaling was performed on dental simulation units using methylene blue dye‐stained water. All resultant stain profiles were photoanalysed to calculate droplet size and travel distance/direction. Airborne particle concentrations were also documented 0–1.2 m (0–4ft.) and 1.2–2.4 m (4–8ft.) from patients during in vivo ultrasonic scaling with a saliva ejector.

Results

Stain profiles showed droplets between 25 and 50µm in diameter were most common, with smaller droplets closer to the mouth. In‐vivo particle concentrations were uniformly low. The smallest (<1 µm, PM1) and largest (>10 µm, PM10+) particles were most common, especially within 1.2 m (4ft.) of the patient. Respirable particles (PM2.5) were uncommon.

Conclusions

Tests showed the highest concentration of small droplets in zones nearest the patient. While uncommon, particles were detected up to 2.4 m (8ft.) away. Furthermore, observed particle sizes were consistent with those that can carry infectious agents. Efforts to mitigate the spread of inhalable aerosols should emphasize proximate regions nearest the procedure, including personal protective equipment and the use of evacuation devices.

The New Normalcy in Dentistry after the COVID-19 Pandemic: An Italian Cross-Sectional Survey

Background: After the first lockdown, Italian dentists resumed their practice while handling several challenges. Reducing contagion risk by complying with the stringent measures recommended by the Italian Ministry of Health for dental activity while also balancing patient needs was a difficult task. This work aims to understand the procedures that were adopted in the second phase of the COVID-19 pandemic (5 May–30 September 2020) and the dentists’ expectations and concerns about returning to normalcy. Methods: A national survey with 38 questions was conducted from November 2020 to January 2021 and comparisons were performed among the five main Italian geographic areas. Results: Located mainly in northwest Italy, 1028 dentists were included in the survey. About 83% of the Italian dentists fully restarted their activities after the lockdown. The resumption was significantly marked in North Italy and the Center than in the South (p < 0.01). Over 80% adopted the recommended precautional guidelines, modifying them according to the specific dental treatment executed. Fifty percent of dentists were confident in returning to normalcy after the COVID-19 crisis. Many precautions adopted during the pandemic will be continued, especially in South Italy and the Islands (p < 0.01). Conclusions: Italian dentists reported excellent autonomous organizational skills and the maintaining of high-quality precautions during the reopening phase.