title: Occurrence and diversity of both bacterial and fungal communities in dental unit waterlines subjected to disinfectants.
abstract: Chemical disinfectants are widely advocated to reduce the microbial contamination in dental unit waterlines (DUWL). However, until now their efficacy has been poorly examined after long-term application. In this study, through quantitative PCR and high-throughput sequencing, both bacterial and fungal communities were profiled from 8- to 12-year-old DUWL treated with disinfectants commonly used by European dentists. Water was collected from the tap water supplying units to the output exposure point of the turbine handpiece following a stagnation period and dental care activity. Results showed that (i) the unit itself is the principal source of microbial contamination and (ii) water stagnation, DU maintenance practices and quality of water supplying DU appeared as parameters driving the water quality. Despite disinfecting treatment combined to flushing process, the microbial contamination remained relevant in the studied output water, in association with a high bacterial and fungal diversity. The occurrence of potentially pathogenic microorganisms in these treated DUWL demonstrated a potential infectious risk for both patients and dental staff. A disinfectant shock before a prolonged stagnation period could limit the microbial proliferation inside DUWL. Necessity to proceed to regular water quality control of DUWL was highlighted.
authors.affiliation: Team Water Microbiology, Ecology and Biology of Interactions, CNRS, University of Poitiers, 86073 Poitiers Cedex, France Bacteriology and Hospital Hygiene Laboratory, University Hospital of Poitiers 86021 Poitiers Cedex, France damien.costa@univ-poitiers.fr.
authors.forename: Damien
authors.initials: D
authors.lastname: Costa
authors.affiliation: Team Water Microbiology, Ecology and Biology of Interactions, CNRS, University of Poitiers, 86073 Poitiers Cedex, France Cooperative Laboratory Thanaplast SP-EBI-Carbios Bioplastics, Ecology and Biology of interactions, CNRS UMR 7267, University of Poitiers 86073 Poitiers Cedex, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Mercier
authors.affiliation: Cooperative Laboratory Thanaplast SP-EBI-Carbios Bioplastics, Ecology and Biology of interactions, CNRS UMR 7267, University of Poitiers 86073 Poitiers Cedex, France.
authors.forename: Kevin
authors.initials: K
authors.lastname: Gravouil
authors.affiliation: Microorganisms laboratory: Genome and environment, UMR CNRS 6023, University Blaise Pascal 63177 Aubière Cedex, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Lesobre
authors.affiliation: Team Water Microbiology, Ecology and Biology of Interactions, CNRS, University of Poitiers, 86073 Poitiers Cedex, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Verdon
authors.affiliation: Team Water Microbiology, Ecology and Biology of Interactions, CNRS, University of Poitiers, 86073 Poitiers Cedex, France University of Medicine Pharmacy of Poitiers 86073 Poitiers Cedex, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Imbert
keywords: Calbenium©; Oxygenal 6©; dental unit waterlines (DUWL); disinfection; pathogens; pyrosequencing