Sir, in spring 2020, Public Health England evaluated the presence of air-borne SARS-CoV-2 as part of a wider investigation into environmental contamination within hospital settings where COVID patients were being treated.1 The authors reported detectable levels of virus in 7.3% of air samples. This study confirms the depth of research capability within the UK scientific community.

It is unclear to us why similar investigations have not taken place in dentistry. It would be important to assess the actual risk of air-borne SARS-CoV-2 transmission in dental practices. These findings may have very significant implications for the prospect of stepping-down current precautionary measures.

Efforts have been made to count airborne particles generated within the dental environment under differing experimental conditions. However, the clinical relevance of counting particles of indeterminate composition remains equivocal. The NHS has previously funded research into dental bio-aerosol.2,3 This was carried out by the Centre of Applied Microbiology & Research - a precursor constituent of Public Health England. We are unsure as to the motivation for the NHS to conduct research into dental bio-aerosol 20 years ago. Equally perplexing are reasons why this fleeting curiosity diminished as quickly as it appeared.

We invite our more learned colleagues to direct us to existing or in-progress studies which seek to resolve the outstanding question of the risks associated with dental treatment during a pandemic.