Department of Public Health, Graduated School of Yeungnam University1
Department of Preventive Medicine and Public Health, College of Medicine, Yeungnam University2
Objectives: The purpose of this study was to investigate the pathogenicity of microorganisms by quantitative and qualitative analysis of microorganisms before and after flushing of dental unit water. Methods: This study was conducted on the supply of high-speed handpieces, ultrasonic scalers, and air-water syringes, which sterilized from 10 dental unit chairs at a dental clinic in South Gyeongsang Province. The number of bacterial communities was calculated by collection before and after flushing (2, 4, and 6 minutes). Results: The mean number of bacteria in the handpiece water before flushing was 27,208 CFU/㎖; 2 minutes after flushing, 2,180 CFU/㎖; 4 minutes after flushing, 900 CFU/㎖; and 6 minutes after flushing, 412 CFU/㎖. Conclusions: To minimize the risk of cross-infection and intra-clinic infection in dental clinics, education and water quality monitoring may be needed.