Thanks for posting an informative thread here but I don't think face masks and air purifiers are enough to safeguard the patients at dental clinics. Actually, last week, I visited Bello Dental in Montebello, CA and found that they are perfectly handling this post-COVID-19 issue. Yes, they are not only using safety products but also overcome the waiting time and prevent the gathering the common or waiting areas. Similarly, they are using hand and area sanitization etc.
Moreover, if any of their staff gets any single sign of COVID, they suggest them to stay at home. Similarly, the same thing they are using for their patients. Yes, I entirely verified them that I don't have any sign of COVID and then I got an appointment. I think other dental clinics should also follow this kind of SOPs.
I also read this article on the 3rd of August, and according to ADA, there was no dental clinic coronavirus case reported in all states of America. Withal, it is still a high-risk industry, and we need to be very careful.