Biofilm in Dental Unit Waterlines

Jackson, Sean D., Valerie Fearn, and Muhammed Farhan


To explain the different kinds of Biofilm found in dental unit waterlines and ways to effectively eliminate Biofilm found in dental unit waterlines.


Biofilms are microbes that adhere to solid surfaces wherever there is moisture. They consist mostly of bacteria, and are usually heterogeneous. They are enclosed in are enclosed in a protective slime layer called a glycocalyx. The potential hazardous pathogens that are found in Biofilm and in waterlines are Pseudomonas aeruginosa which can cause pneumonia, Legionella pnemophilia which causes Legionnaries’ disease and Pontiac fever, and nontuberculous Mycobacterium which is associated with pulmonary disease and wound infection. In order to prevent the exposure of Pseudomonas, Legionella, and nontuberculous mycobacterium the waterlines should be cleaned daily. The Centers for Diseases Control recommends flushing waterlines daily for several minutes and flushing waterlines 20 to 30 seconds between patients. Along with flushing the waterlines daily there must be other methods to reduces harmful bacteria in waterlines. One method recommended is the use of Dentapure, which is used at the University of Detroit-Mercy and is ADA approved to reduce Biofilm in the waterline of less than 200 CFU. Another method recommended is the use of the waterclave. The waterclave is FDA approved with the claim of reducing Biofilms to 0 CFU.


Understanding what Biofilm is how Biofilm forms in dental unit waterlines and ways to effectively eliminate Biofilm in water unit waterlines is very important in dental hygiene practice. Every hygienist and dentist should understand the relevance of Biofilm in waterline and ways to prevent the potential spread of hazardous pathogens to themselves and patients.