DUWLs seem to be all the rage these days – whether that’s because of new research or because they can become a real frustration for dental pro’s is another discussion.
On the surface, it can seem easy to tell the treatment options apart from application, duration, and complexity, but these differences only get you so far if one thing is unclear: getting dental unit waterlines clean is what matters.
With lots of confusion out there, we wanted to share our lab’s research from over 40,000 consecutive dental unit waterline tests in 2017 showing the effectiveness of dental water maintenance products in real-world situations (which has been cited in a peer-reviewed article by John A. Molinari and Nancy Dewhirst). All of these tests were from practices across the United States reporting their protocols testing their lines – we simply collected the data.
So, first, let’s make sure we understand what kind of treatments are available, what makes them unique, and then, how effective they are in real dental practices.
All of the FDA or EPA registered continuous treatment products available on the market today utilize low-level antimicrobials to control microbial growth. The most popular of which utilize silver and iodine chemistries. These low-level antimicrobials are generally in a concentration of in parts per million (PPM). Similarly, Chlorine is often used in city water and pools to control bacteria is typically 1-2 ppm. Iodine-based products are typically .5 – 4 ppm and silver based technologies are typically .5-1 ppm.
These low-level antimicrobials are designed to be continuously present in your dental waterlines to constantly attack microbacterium. These can be introduced into your lines by three standard methods: tablets, cartridges, and daily liquids. Because they are continuously present in the lines as well as the irrigant water (procedural water) and sprayed in the patient’s mouth, they are by necessity designed to have very low concentrations of antimicrobial agents for patient safety.
Unfortunately, the failure rate of all of treatment products together is still 30%. The reason is that following the instruction is critical. Compare that to sterilizers used on instruments where the fail rate is only 1.5%. Whichever water treatment product you select, it is important that you carefully follow the instructions and test your maintenance protocol at least quarterly to ensure success.
The shock product category is comprised of high level antimicrobials. They can remove well established biofilms even in dental units that have been operated for years without being subjected to any antimicrobial treatments. Since bacteria will multiply within a few days, routine treatment with a shock product as the only treatment requires weekly shocking of every line.
Continuous Treatment Products
The most popular treatment method is a tablet that is added to the independent reservoir each time it is refilled with water. Roughly 11 million tablets are used by U.S dentists each year. This the most common method of treating dental unit waterlines. If you consumed 200 liters per operatory per year the annual cost would be $91 (200 liters x .45 cents per 2 liter tablet). Simply, it’s economical and one of the more effective treatment types.
Cartridges are small resin filled with iodine or silver chemistries that release a low-level antimicrobial into the water as water passes through the cartridge. They are designed to replace the take-up straw in your independent reservoir. Cartridges range in cost from $245-252 per year per operatory. The most popular straw is designed to last for 1 year or 240 liters of water, whichever comes first.
Daily liquids is a category that includes Chlorhexidine Gluconate, citrus botanicals, and chlorine dioxide based chemistries. They are added to the independent water bottle each time it is refilled. This one of the least popular methods and accounts for about 5% market share. The costs per year range from $104 to $217 per operatory.
The most popular shock products are household bleach and Sterilex Ultra. Both products are effective at removing/killing biofilms. Many OEM equipment manufacturers recommend diluted bleach or sodium hypochlorite (13 parts water to one-part bleach). Sterilex is a quaternary ammonium compound and hydrogen peroxide based chemistry. Shock products make up 4% of the market. The cost to treat an operatory for a year ranges from $3 for bleach and $117 for Sterilex Ultra.
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Selecting the Right Product and Maintenance Program for Your Practice
The vast majority of the dentists use tablets and straws. The main reason is tablets and straws (continuous treatment) are economical, can provide good results and are convenient. Straws and tablets will inhibit the proliferation of bacterial growth and ultimately biofilms, but they will not render the lines and water sterile.
Tablets are effective as long as you follow the instructions. Tablets require a periodic shock (every 1 to 3 months). Add a tablet every time you refill the water bottle. Shock your dental unit waterlines as recommended by the manufacturer and test for microbial counts regularly. Tablets combined with at least quarterly shocking provides highest level of effectiveness.
Cartridges are represented as having one-year use-life. Cartridges are an effective method of delivering low level antimicrobials. Always start the use of a cartridge with clean/shocked lines. Cartridges manufactures instructions for use include important parameters on the hardness of the water, concentration of chlorine in source water, the temperature of the water. Follow the instructions. Failing to do so can result in a failure to meet the ADA/CDC standard for clean water. Test water quality quarterly.
This class of product is about 5% of market and does provide low level antimicrobials to the dental unit waterlines, however, the data indicates that the actual effectiveness results are the lowest category tested. Do your research, follow instructions and test for microbial counts quarterly to verify performance.
Shock products used correctly are very effective. Follow the IFU’s and test regularly. If you use household bleach, a 13 to 1 dilution and 10 minutes or less exposure time is recommended.
Is Your Treatment Working?
These tests reveal that even the most effective dental water treatment protocols, the possibility of microbial contamination remains. That’s why testing becomes vital.
“The only way to ensure effectiveness of a dental unit waterline cleaning regimen is to actually test the water coming out of the unit.” – American Dental Association
We recommend all dental clinics test their dental waterlines quarterly to ensure dental water treatments are working properly and your patients and practice are safe.
Download a PDF of the Product Selection Guide Here:
All of the statements in this article are based on the data from 40,000 consecutive water tests conducted by ProEdge Dental Water Labs in 2017. ProEdge has been testing dental water for 15 years and works closely with dental offices to correct failed water tests. The effectiveness data is derived from test data provided by hundreds of dental practices. The data is reported in this article the same way it is reported to our lab. The data contained in this paper is based on 40,000 water tests and indicates how a product is performing in the marketplace. It does not guarantee that any particular product will perform exactly as the effectiveness data is reported. For more detail information on dental unit water testing, contact our team or call today at 888.843.3343.