Excellent question. I did a little looking tonight. The first thing that popped up was a cluster of dental workers with idiopathic pulmonary fibrosis, possibly related to occupational exposure. Not the same thing but not entirely unrelated.
https://www.ada.org/en/publications/ada-news/2018-...This 20-year-old Canadian paper was the most directly related:
Risk of Transmission of Viruses in the Dental Office
"...Seroprevalence studies have shown a higher prevalence of antibodies to influenza A and B viruses, respiratory syncytial virus and adenovirus among dentists compared with controls."
http://www.cda-adc.ca/jcda/vol-66/issue-10/554.htm...Most of what I found discussed infection risk in dental offices from multiple perspectives: patient->dentist, dentist->patient and patient->next patient in the same room. Not surprisingly, there is more concern about the patients staying healthy than their health care providers! This is an example.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC33751...