No way I would have let them treat me..
Laying below an improperly masked hygienist (sharing air with how many patients in a week?) with my airway Agape for 20 minutes?
Hard no.
I called my dentist last week. Offered to give them some face shields and we got to talking masks. They sent me pics of the masks they're using. I was able to trace them back to a Chinese factory that makes children's clothing and has no certificates for mask production.
My teeth can wait a few months more.