Assessment of atmospheric microbial contamination in a mobile dental unit

Bioaerosols are important considerations in infection control as well as in occupational health. Bioaerosols may carry potentially hazardous microbes, viruses, fungi, allergens, and other toxic substances that may harm the dental operator, patient, and the dental assistant by causing nosocomial infections.

To assess the level of atmospheric microbial contamination before, during, and after dental treatment procedures in the dental operatory of a mobile dental unit (MDU).

The study included three treatment sessions on different working days, with an interval of one month. The MDU was fumigated before the start of the study. Brain Heart Infusion Agar with 5% sheep blood was used to collect the gravitometric settling of aerosols produced before, during, and after dental treatment procedures. The agar plates were sent for aerobic and anaerobic culture.

The results showed that atmospheric microbial contamination (CFUs/plate) was 4 times higher during working sessions as compared to the levels before the working sessions. At the end of the working day, aerosols decreased by almost 3 times that seen during work.

The aerosols increased during and after work sessions. This shows the increased risk of transmission of infectious agents to the dentists who work in the MDU. Hence, all necessary preventive measures should be advised and need to be followed strictly.