be if the building in which the clinic is situated, such as a hospital, has a complex water system, or if the water supply to the clinic is accidentally contaminated with bacteria as a result of renovations and repair. It is recommended that the water in DUWLs is specifically checked after such accidents. Another clinic-related problem is when the clinic has insufficient routines or has chosen an insufficient method for water cleaning.
Conclusions
Biofilm formation and a high number of microorganisms in the output water of DWULs has been a main concern in dental practice for several decades. Today, most brands of dental units are equipped with in-built methods for reducing the number of microorganisms and/or eliminating biofilms. For older units, means of cleaning the water are available on the market and have a good efficiency. Ultimately, it is the handling and compliance with instructions rather than the cleaning procedure itself that determines whether a clinic maintains an appropriate standard of water in its dental unit systems.
Acknowledgements
Mrs. Susanne Blomqvist is gratefully acknowledged for fruitful discussions during preparation of the manuscript.
Conflict of Interest Statement
The author has no conflicts of interest to declare.
Funding Sources
No funding was raised or used for preparing this paper.
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