In 1993, CDC recommended that dental waterlines be flushed
at the beginning of the clinic day
to reduce the microbial load (2). However, studies have demonstrated this practice does not affect biofilm in the waterlines or reliably improve the quality of water used during dental treatment (315,338,343).
What microbes are of concern in dental unit water lines?
The most frequently found genera of bacteria in DUWLs, regardless of their origin, are
Pseudomonas, Legionella, Klebsiella, Moraxella, Flavobacterium and Escherichia or non-tuberculous mycobacteria
(NTM; Schulze-Robbecke et al., 1995; Pankhurst et al., 1998; ADA, 2000; Castiglia et al., 2008).
What is the maximum number of microbes CDC says should be in dental unit water used for patient treatment?
The CDC recommends that dental unit water used in nonsurgical procedures measure
less than or equal to 500 colony forming units of heterotrophic bacteria per milliliter
(≤500 CFU/mL) of water, the standard set for drinking water by the Environmental Protection Agency (EPA).
How many colonies should contain a dental water unit?
Water companies are required to keep them within the very strict limit of
100 Colony Forming Units
(CFUs). These organisms are part of ‘ biofilms’ which form rapidly in dental waterlines because: there is a source of nutrients for the bacteria.
What waterborne bacteria are of most concern in dentistry?
As a result, high numbers of common water bacteria can be found in untreated dental unit water systems. A few disease-causing microorganisms found in untreated dental unit water include Legionella,
Pseudomonas aeruginosa
, and nontuberculous Mycobacterium.
How long should you flush dental lines?
At the beginning of each workday, dental unit lines and devices should be purged with air or flushed with water for at least two minutes prior to attaching handpieces, scalers, air water syringe tips or other devices. The dental unit lines and devices should be flushed between each patient for
a minimum of 20 seconds
.
How often should dental lines be flushed?
Frequency and usage is key to biofilm formation. Water movement in DUWLs is stagnant 85% of the time so if a chair is then only used for a couple of days a week this can contribute to biofilm formation. Flushing
twice a day as a
minimum is a requirement to ensure fresh Alpron is in the lines.
Can viruses multiply in dental water lines?
Several studies have revealed that dental unit waterlines (DUWLs) are often contaminated by large numbers of various micro-organisms (bacteria, fungi, protozoa, viruses).
What are the 5 stages of biofilm formation?
Biofilm formation can be divided into five stages:
Initial reversible attachment (1), irreversible attachment (2-3), maturation (4) and dispersion (5)
as shown in Figure 2. The initial contact of the moving planktonic bacteria with the surface is the starting point, which is still reversible at this stage.
What is waterline dental?
The waterlines of a dental unit, typically constructed from a polymer (e.g. polyurethane, polyvinyl chloride) or silicone rubber tubing,
provide water from its source for irrigation, cooling, and flushing of the patient’s oral cavity during dental procedures
.
What is the maximum acceptable level of bacteria in dental unit water?
Background: The maximum recommended level of microbial contamination of water from dental unit waterlines (DUWL) is
200 colony-forming units per milliliter (CFU/mL)
. This article addresses the importance of water selection in achieving that standard.
What type of water do dentists use?
Use
sterile saline or sterile water
as a coolant/irrigant when performing surgical procedures.
Which accepted methods reduce the number of bacteria in dental waterlines?
The American Dental Association recommends that dental treatment water should contain no more than 200 CFU/ml.
Chemical agents, filtration, and independent water reservoirs
are effective measures to reduce the bacterial load to the recommended level.
Why should you flush water through dental unit waterlines between patients?
In 1993 the U.S. Centers for Disease Control and Prevention (CDC) recommended that dental water lines be flushed
to reduce the microbial load in dental unit water
. … Exposure to dental water has not been shown to present a demonstrable health risk to either patients or dental health care providers.
Will flushing dental unit waterlines remove biofilm?
It is recommended
to flush waterlines for 20 to 30 seconds after each patient
. While flushing the waterlines can reduce the microbial load, the effects are temporary. Bacterial counts can quickly rise to levels that equal or exceed pre-flush levels as biofilm grows or is dislodged by flowing water.
What are the factors in bacterial contamination of dental unit water?
A high level
of microbial contamination, presence of opportunistic microorganisms and bacterial endotoxin associated with Gram-negative bacteria
are the most important health risk factors transmitted by water from dental units (Szymańska et al.
