The abundance of the potential pathogen Staphylococcus hominis in the
air microbiome in a dental clinic and its susceptibility to far-UVC
The dental clinic air microbiome incorporates microbes from the oral
cavity and upper respiratory tract (URT). This study aimed to establish
a reliable methodology for air sampling in a dental clinic setting and
quantify the abundance of culturable mesophilic aerobic bacteria present
in these samples using regression modeling. Staphylococcus hominis, a
potentially pathogenic bacterium typically found in the human oropharynx
and URT, was consistently isolated. S. hominis was the most abundant
species of aerobic bacteria (22% to 24%) and comprised 60% to 80% of
all Staphylococcus spp. The study also assessed the susceptibility of S.
hominis to 222nm-far-UVC light in laboratory experiments, which showed
an exponential surface inactivation constant of k = 0.475 cm2/mJ. This
constant is a critical parameter for future on-site use of far-UVC light
as a technique for reducing pathogenic bacterial load in dental clinics.