Aerosol exposure of staff during dental treatments: a model study.

BACKGROUND: Due to exposure to potentially infectious aerosols during treatments, the dental personnel is considered being at high risk for aerosol transmitted diseases like COVID-19. The aim of this study was to evaluate aerosol exposure during different dental treatments as well as the efficacy of dental suction to reduce aerosol spreading. METHODS: Dental powder-jet (PJ; Air-Flow®), a water-cooled dental handpiece with a diamond bur (HP) and water-cooled ultrasonic scaling (US) were used in a simulation head, mounted on a dental unit in various treatment settings. The influence of the use of a small saliva ejector (SE) and high-volume suction (HVS) was evaluated. As a proxy of aerosols, air-born particles (PM10) were detected using a Laser Spectrometer in 30 cm distance from the mouth. As control, background particle counts (BC) were measured before and after experiments. RESULTS: With only SE, integrated aerosol levels [median (Q25/Q75) µg/m3 s] for PJ [91,246 (58,213/118,386) µg/m3 s, p < 0.001, ANOVA] were significantly increased compared to BC [7243 (6501/8407) µg/m3 s], whilst HP [11,119 (7190/17,234) µg/m3 s, p > 0.05] and US [6558 (6002/7066) µg/m3 s; p > 0.05] did not increase aerosol levels significantly. The use of HVS significantly decreased aerosol exposure for PJ [37,170 (29,634/51,719) µg/m3 s; p < 0.01] and HP [5476 (5066/5638) µg/m3 s; p < 0.001] compared to SE only, even reaching lower particle counts than BC levels for HP usage (p < 0.001). CONCLUSIONS: To reduce the exposure to potentially infectious aerosols, HVS should be used during aerosol-forming dental treatments.

Implementation of COVID-19 Infection Control Measures by German Dentists: A Qualitative Study to Identify Enablers and Barriers.

OBJECTIVES: COVID-19 infection control measures have been recommended for dental practices worldwide. This qualitative study explored barriers and enablers for the implementation of these measures in German dental practices. METHODS: Semi-structured phone interviews were conducted in November/December 2020 (purposive/snowball sampling). The Theoretical Domains Framework (TDF) and the Capabilities, Opportunities and Motivations influencing Behaviors model (COM-B) were used to guide interviews. Mayring's content analysis was employed to analyze interviews. RESULTS: All dentists (28-71 years, 4/8 female/male) had implemented infection control measures. Measures most frequently not adopted were FFP2 masks, face shields (impractical), the rotation of teams (insufficient staffing) and the avoidance of aerosol-generating treatments. Dentists with personal COVID-19 experience or those seeing themselves as a role model were more eager to adopt measures. We identified 34 enablers and 20 barriers. Major barriers were the lack of knowledge, guidelines and recommendations as well as limited availability and high costs of equipment. Pressure by staff and patients to ensure infection control was an enabler. CONCLUSIONS: Dentists are motivated to implement infection control measures, but lacking opportunities limited the adoption of certain measures. Policy makers and equipment manufacturers should address these points to increase the implementation of infection control measures against COVID-19 and potential future pandemics.

Comment on "Endothelial Protein C Receptor (EPCR), Protease Activated Receptor-1 (PAR-1) and Their Interplay in Cancer Growth and Metastatic Dissemination" Cancers 2019, 11, 51.

Although the interplay between tumor progression and blood coagulation has been recognized [...].