Contamination of a Dental Unit Water Line System by Legionella Pneumophila in the Mashhad School of Dentistry in 2009

Dental unit waterline system is considered potential source for contamination with Legionella species. The aim of this study was to determine if contamination of a dental unit water line system by Legionella pneumophila serogroup1 in the Mashhad School of Dentistry occurred in 2009.. A total of 52 dental units were selected from all clinical departments of the Mashhad School of Dentistry. Samples of water were collected from outlets of water/air spray, high-speed dental hand pieces and water cup fillers. Samples were tested via the ELISA method.. At the beginning of the work day, a total of 36.1 percent of dental units were contaminated by Legionella pneumophila serogroup 1.. Infection control of the dental unit water line system regarding legionella in the Mashhad School of Dentistry is a challenge and engineering controls should be used in contaminated clinics.