Isolation of filter passing bacteria from a range of dental clinic surfaces; pp. 98–101

Full article in PDF format | 10.3176/proc.2021.1.08

Saleh H. Salmen, Hesham S. Almoallim, Eman Damra, Tahani Awad Alahmadi, Sulaiman Ali Alharbi


Filter passing bacteria have been isolated from a variety of natural environments, appearing as a mixture of  Gram-positive and Gram-negative, as well as nano-forms and wall-free species. In this study, filter passing bacteria were isolated from surfaces located in various dental departments at the College of Dentistry, King Saud University Hospital. Surface samples were obtained by using Q-tip swabs, with ten different surfaces being sampled in each clinic during pre-patient and post-patient visits. Filterable bacteria (using 0.4 and 0.2 micron filters, but not 0.1 micron filter) were isolated, being mainly Gram-positive cocci. Isolation results of filterable bacteria were compared before and after patient treatment in the clinic. More frequently, filter passing bacteria were isolated on clinic surfaces after patient treatment.  The results show that dental settings are contaminated with filterable bacteria which may act as a reservoir for the wider contamination of hospital environments.


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