Isolation of selected possible aerobic bacterial pathogens from dental environmental surfaces after use of disinfectants - A case study at a public dental clinic, in KwaZulu-Natal

Keywords: infection control, disinfectants, dental environment, bacteria, cross-infection, contamination


Cross infection in the dental clinical environment remains a low priority in conversations around oral health care despite the high risk of exposure to blood and airborne infections. The aim of this study was to determine the presence of selected pathogens after use of disinfectants on specific dental environmental surfaces at a public oral health facility in KwaZulu-Natal. This was a cross-sectional descriptive case study with a non-experimental design. The dental clinical environment was divided into four zones and 9 dental units were systematically selected. Swabs were collected from the 26 identified areas at specific time intervals (7.00, 9.00, 11.00, and 16.00) after the use of chlorine, ethanol (70% in water) and glutaraldehyde (2%) as surface disinfectants. The collected swab samples were cultured in nutrient agar media for two days at 37°C. The colony forming units were then examined and characterized using the MALDI-TOF spectrometer. Out of the 312 samples taken, 262 (84%) were shown to be bacterial culture positive. The most contaminated areas in the dental environment were around the chair area (86.53%) and the area away from the chair (92%). Glutaraldehyde was found to be more effective than chlorine and ethanol. The study suggests an association between the frequency of cleaning, the type of disinfectant used and the bacterial microbial count on the specified dental environmental surfaces at the identified oral health facility.


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How to Cite
Deulkar, S., Singh, S., & Tiwari, D. (2020). Isolation of selected possible aerobic bacterial pathogens from dental environmental surfaces after use of disinfectants - A case study at a public dental clinic, in KwaZulu-Natal. South African Dental Journal, 75(5), 241-246.