A webpage published recently by the Food and Drug Administration provides guidance on infection control in dental unit waterlines. Dental unit waterlines are regulated by the FDA, and although they typically cannot be sterilized, “they should be routinely cleaned and disinfected” to prevent risk of infection to patients, “particularly during surgical procedures by direct exposure of waterborne pathogens and to dental professionals due to inhalation of aerosols,” the FDA says.

Included on the dental unit waterlines webpage are more than a dozen tips and “do’s and don’ts” for dental practitioners, including:

• Discharge water and airlines for a minimum of 20-30 seconds after each patient to physically flush out patient material that might have entered the dental water system during treatment.
• Be alert to signs that may indicate biofilm formation including musty odor, cloudiness or particulates in the water, and clogging of lines.
• Do not attach dental handpieces or dental instruments to dental unit waterlines that have not been cleaned or disinfected per the manufacturer’s instructions.

Dentists and dental professionals should also ensure that they follow the Dental Board of California’s infection control requirements related to cleaning and maintaining dental unit waterlines. These requirements state: “At the beginning of each workday, dental unit lines and devices shall be purged with air or flushed with water for at least two (2) minutes prior to attaching handpieces, scalers, air water syringe tips, or other devices. The dental unit lines and devices shall be flushed between each patient for a minimum of twenty (20) seconds.”

The FDA webpage provides additional recommendations for manufacturers of dental unit waterlines.