Dentists are encouraged to take steps to reduce any potential risk of dental unit waterline microorganisms causing infection through the following waterline maintenance procedures:

• 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 water.

• Use sterile water or sterile saline when flushing open vascular sites and/or cutting bone during invasive surgical procedures.

• Follow manufacturer’s 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