Years ago, in an attempt to combat the issue of microbial contamination of dental unit waterlines, dental delivery system manufacturers introduced independent bottle systems. As you probably know, these bottle systems provide delivery units with an independent source of water not connected to the city water supply. These dental bottles typically hold between 750mL to two liters of water.

Your dental unit waterlines are very likely contaminated. Dental unit waterline problems result mainly from how water is used in the operatory, and the design of dental delivery units.

Due to the nature and complex design of dental delivery units, the periodic use of waterline cleaners and antimicrobial agents is extremely important for proper dental waterline care. As mentioned earlier, even sterile water introduced to dental delivery systems can become contaminated very quickly and exceed CDC and ADA-recommended guidelines for maximum microbiological contaminant levels of 500 CFU/mL.

Regardless of whether dental operatories are plumbed directly to municipal water supply lines or utilize independent bottle systems—and regardless of the presence or absence of any water filtration system that might be installed—the following protocols and guidelines should be observed at all times for dental waterline maintenance:

We've discussed some of the factors that contribute to the problem of microbiological contamination in dental unit waterlines. In this brief article, we’ll outline the dental waterline standards in place for microbiological water quality. In order to verify compliance with these guidelines, dental practices should spot-check their water quality throughout the operatory environment at least quarterly by submitting water samples to a laboratory for HPC testing, or by using some type of in-office testing product.

There’s a good chance that thousands—if not millions—of microorganisms are present in the water dental practitioners use with their patients every day. Even very low levels of bacteria commonly present in treated city water can increase exponentially in dental unit waterlines.

Did you know that minerals and contaminants commonly present in city water supplies make tap water a poor choice for use in dental bottles and delivery systems? Whether your delivery unit is plumbed directly to a water supply or uses an independent bottle system, using tap water in dental unit waterlines isn’t ideal.