ntroduction. Patients and operators are exposed during dental practice to an infective risk, which derives especially from micro- organisms suspended in aerosols. Environmental microbiologi- cal monitoring in dental settings represents a good instrument to detect critical situations.
Methods. In order to investigate environmental microbial contami- nation level in a local reality, we analyzed water, air and surfaces samples of a community-based dental facility by using protocol and threshold values proposed in a recent multicenter study carried out by the Italian Society of Hygiene, Preventive Medicine and Public Health (S.It.I.) working group ?Hygiene in Dentistry?. Microbial contamination was assessed in the same room for 4 non-consecu- tive weeks during all the five working days, before and at the end of the daily activity. Air was sampled also during clinical activity, through both active and passive sampling systems.
Results. Contamination of water showed a decrease during activ- ities, while a decrease in air contamination was registered only at the end of the day. Passive sampling values resulted more often above threshold values adopted. At the same time, surfaces con- tamination increases at the end of the activity. It seems that in the dental clinic analyzed microbial buildup represents the higher critical element. No differences have been registered among the different days of the week.
Discussion. Our study highlights the need to improve disinfection procedures and air treatment systems in the considered environ- ment. Microbiological monitoring could represent an important element to detect the presence of risk factors and to adopt control measures.