Surface microbial contamination in a dental department. A 10-year retrospective analysis

Health care-associated infections may not only occur in a hospital setting, but also in dental clinics. Insufficient environmental decontamination could be one of the risk factors. In this retrospective study, we documented and analyzed the results of surface microbial contamination in a dental university-based department over an observation period of ten years. It was the aim of this investigation to identify general tendencies and potentially problematic sites on a long-term basis allowing suggestions for further improvement. Surface microbial contamination in the Department of Reconstructive Dentistry at the University Center for Dental Medicine in Basel, Switzerland, was evaluated on a regular basis using contact plates. Data gained between January 2007 and December 2016 was collected and summarized for statistical analysis. Although the overall surface microbial contamination was relatively low during the observation period, significant differences depending on localization and test sites were detected. Certain sites, such as the handle of the dentist’s chair and computer surfaces, remained problematic. Continuous monitoring of surface microbial contamination can help to improve the hygiene level in a dental set-up. Further improvement might be achieved by avoiding hand-touch handles whenever possible and by relying on flat and easy-to-clean surfaces within the reach of the bacterial aerosol. However, during interventions that may pose a higher risk for the patient, additional measures should be taken by working under almost sterile conditions and by avoiding direct hand contact with problematic sites.