Legionella in the dental practice: Self-control through regular water analyzes
The dentists’ water systems in Swiss dental practices are sometimes heavily contaminated with germs. The hygiene in the dental practice can be actively improved through water tests and hygiene management.
The water quality in dental treatment units: a topic that has been discussed for years because it is inadequate in many Swiss dental practices. Of over 260 samples from 21 dental practices in German-speaking Switzerland, almost 60 percent were heavily contaminated with germs last year. Many samples had values of tens to hundreds of thousands of colony forming units (CFU) per milliliter of water. For comparison: the legal upper limit of 300 CFU/ml applies to drinking water.
Since there are no binding legal standards, the dental practices themselves have to take action and establish reliable hygiene controls – for example through cooperation with independent analysis laboratories such as Biolytix. With “Dentalytix”, the laboratory for molecular biological and microbiological analysis has specialized in testing the quality of the water in dentist chairs and in comprehensive hygiene monitoring for dental practices and dental hygiene businesses.
Legionella in dental practices – dental units provide an ideal breeding ground
As so-called environmental germs, Legionella can be detected in almost all natural humid environments in mostly small quantities. On the other hand, artificial man-made water systems offers them best conditions to multiply extensively. The legionella concentration in the water is strongly dependent on temperature, the bacteria prefer values between 25 and 45 degrees Celsius. The numerous small tubes through which the fresh water runs within the dental equipment of a dental practice, form an ideal breeding ground for the Legionella pneumophila bacterium.
Dental treatment often results in minor injuries or larger wound areas in the oral cavity, through which various germs can get into the human bloodstream. In addition, the water is atomized into fine aerosols during dental treatment by rapidly rotating devices such as the drill. These aerosols are absorbed through the respiratory tract and are a frequent route of infection for the life-threatening Legionnaires’ disease. Lung disease caused by Legionella has increased in Switzerland in recent years.
In 2019, 582 cases of Legionnaires’ disease were recorded; five to ten percent of the diseases were fatal.
Comprehensive practice hygiene and regular water analyzes by independent laboratories
In response to the increasing number of diseases caused by Legionella, the FSVO, which is responsible for drinking water, set two maximum values for Legionella in water from sanitary facilities in 2017 – these are regulated in the food legislation.
However, there are no binding standards based on defined limit values – such as for the bacterial load in water systems in dental practices. Dental practices are also not obliged to test the water quality regularly. The problem of contaminated water in dentists’ chairs has been known for a long time and is not limited to Switzerland. In Germany, for example, Legionella was detected in every fourth dental chair in 2013 by the Hessian Center for Health Protection.
So what can practices do to improve water hygiene and thus protect the health of patients and practice employees? – In addition to the daily rinsing of the dental units for at least three minutes before starting work, the cooperation with independent analysis laboratories such as Biolytix serves to prove correct operation through regular water tests. The company offers comprehensive hygiene monitoring for dental practices and dental hygiene businesses. The professional cleaning of surfaces and devices as well as the water quality on the dentist’s chairs and the hygienic status of the hands of the staff are tested. The total number of germs can be reduced by taking appropriate measures.
At least once a year, the water in dental units should be microbiologically examined using water tests – embedded in a comprehensive hygiene plan for dental practices. As a long-term goal, the practice staff must be given guidelines that have long been used for the sterilization of practice devices, for example. Clear guidelines and checklists are required in order to document the tests of the water and therefore the water hygiene, to reduce the total number of germs in the future and to actively contribute to the prevention of Legionella diseases through reliable hygiene controls.
It is very important to adhere to the hygiene standards, especially during the corona pandemic. That is why we recommend regular hygiene checks! We are happy to answer any questions you may have.