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Is there a guideline for water bottles for the dental chair - tap water or distilled? Which is recommended?

Dental unit waterlines should be maintained in strict compliance with the manufacturer’s validated instructions for use (IFU). Failure to do so could result in voiding of the product warranty. Further questions about the IFU should be directed to the dental unit manufacturer.

The 2003 CDC guidelines for infection control in dentistry states:

Maintenance and Monitoring of Dental Unit Water

DHCP should be trained regarding water quality, biofilm formation, water treatment methods, and appropriate maintenance protocols for water delivery systems. Water treatment and monitoring products require strict adherence to maintenance protocols, and noncompliance with treatment regimens has been associated with persistence of microbial contamination in treated systems (345). Clinical monitoring of water quality can ensure that procedures are correctly performed and that devices are working in accordance with the manufacturer’s previously validated protocol.

Dentists should consult with the manufacturer of their dental unit or water delivery system to determine the best method for maintaining acceptable water quality (i.e., <500 CFU/mL) and the recommended frequency of monitoring. Monitoring of dental water quality can be performed by using commercial self contained test kits or commercial water-testing laboratories. Because methods used to treat dental water systems target the entire biofilm, no rationale exists for routine testing for such specific organisms as Legionella or Pseudomonas, except when investigating a suspected waterborne disease outbreak (244). ¹

The 2016 CDC Summary states:

All dental units should use systems that treat water to meet drinking water standards (i.e., ≤ 500 CFU/mL of heterotrophic water bacteria). Independent reservoirs—or water-bottle systems—alone are not sufficient. Commercial products and devices are available that can improve the quality of water used in dental treatment. Consult with the dental unit manufacturer for appropriate water maintenance methods and recommendations for monitoring dental water quality. During surgical procedures,¹ use only sterile solutions as a coolant/irrigant using an appropriate delivery device, such as a sterile bulb syringe, sterile tubing that bypasses dental unit waterlines, or sterile single-use devices.²

Additional information about dental unit waterlines can also be found on the American Dental Association website at https://www.ada.org/en/member-center/oral-health-topics/dental-unit-waterlines³

There may be regulatory requirements in your state that Ask OSAP is not aware of. It is recommended that you also contact your state dental board and state public health agency (i.e., state health department) to find out about any state-specific requirements.

Resources

1) Kohn WG, Collins AS, Cleveland JL, Harte JA, Eklund KJ, Malvitz DM, Centers for Disease Control and Prevention (CDC). Guidelines for infection control in dental health-care settings—2003. MMWR Recomm Rep 2003;52(RR-17):1-61. http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5217a1.htm Accessed on December 7, 2018.

2) Centers for Disease Control and Prevention. Summary of Infection Prevention Practices in Dental Settings: Basic Expectations for Safe Care. Atlanta, GA: US Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Division of Oral Health; March 2016 http://www.cdc.gov/oralhealth/infectioncontrol/pdf/safe-care.pdf Accessed on February 6, 2018

3) American Dental Association. Dental Unit Waterlines. https://www.ada.org/en/member-center/oral-health-topics/dental-unit-waterlines Accessed on December 7, 2018.