Review article
Waterborne pathogens and dental waterlines

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The nature of biofilms

Biofilms are complex, symbiotic microbial communities that almost certainly evolved early in Earth's history and existed for billions of years before the rise of eukaryotes [21]. Biofilms flourish wherever water and solid surfaces exist, ranging from abyssal ocean depths to temporary ponds and rivulets on snow-clad mountain peaks. Human beings are themselves naturally colonized by biofilms (eg, dental plaque) [21], [22].

Bacteria are the basic building blocks of biofilms and provide essential

Biofilm and dental equipment design

Dental waterlines provide an environment conducive to rapid proliferation of biofilm. Biofilm-forming bacteria appear to favor hydrophobic nonpolar surfaces [25]. Planktonic organisms suspended in the bulk fluid quickly colonize the chemically inert waterlines [7], [15]. Motile bacteria respond to chemical stimuli and move toward attractants consisting of low-molecular-weight organic matter [30]. Organic conditioning films quickly form on water-bearing surfaces and serve as a locus for

Dental waterlines and health

As a consequence of the processes previously described, water used for dental treatment becomes contaminated with microorganisms and their metabolic by-products. From the earliest observation of bacteria in water produced by dental units, researchers have expressed concern that patients could become infected by exposure to contaminated water or aerosol [38]. Many of the predominantly gram-negative bacteria isolated from dental water sources are recognized as opportunistic pathogens [22], [39].

Summary

Humans, like every other living thing on Earth, have evolved in a world dominated by many billions of microscopic life forms. Most of the time, we live in a state of harmony (or even mutualism) with our invisible coinhabitants. When this balance becomes disturbed however, the consequences can be devastating. Infectious diseases including malaria, tuberculosis, and AIDS remain the world's greatest mass murderers.

Dental workers strive to reduce infection risks for their patients through infection

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    The opinions expressed in this article are those of the author and do not necessarily reflect the official position of the United States Air Force or the Department of Defense.

    Financial disclosure statement: Dr. Mills is coinventor of the Air Controlled Sterile Irrigation System. US Patent No. 5,700,147.

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