Table 1 CDA Guidelines On Dental Unit Waterline Maintenance
Dentists are encouraged to take steps to reduce any potential risk of dental
unit waterline microorganisms causing infection through the following waterline
- Avoid heating water for the dental unit.
- At the beginning of each clinic day, purge all lines by removing handpieces, air/water
syringe tips and ultrasonic tips and flushing thoroughly with water. The decrease in
bacterial counts associated with such purging has been confirmed in two Canadian studies.1,2
According to Barbeau et al1., 1996, and Whitehouse et al2., 1991,
approximately a 5-8 minute purge is required to reduce bacterial counts to potable water
standards (<500 cfu/ml).
- Run high speed handpieces for 20-30 seconds after each patient, to purge all air and
- Use sterile water or sterile saline when flushing open vascular sites and/or cutting
bone during invasive surgical procedures.
- Follow manufacturers instructions for daily and weekly maintenance if using
bottled water or other special delivery system.
1 Barbeau, J., Tanguay, R., Faucher, E. et al. Multiparametric analysis of waterline
contamination in Dental Units. Appl Envrion Microbiol. 62:3954-3959, 1996
2 Whitehouse R.L.S., Peters, E., Lizotte, J. et al. Influence of biofilms on microbial
contamination in dental unit water. J Dent. 19:290-295, 1991
Approved by Resolution 97.72 CDA Board of Governors