Development of small-scale water fluoridation equipment.

PURPOSE: A water fluoridation program launched in the United States in 1945 has become a worldwide application for caries prevention. Although such a program is important in Japan, water fluoridation in large communities has not been established. This study aimed to develop safe small-scale water fluoride equipment that can be easily used to carry out water fluoridation programs in areas with children in long-term care facilities, and in developing countries without water supply facilities. METHODS: Batch-type NaF addition adjustment equipment was manufactured as small-scale water fluoride equipment. The fluoride concentration of the adjusted water with this equipment was measured using an ion meter and a fluoride composite electrode. All 51 water quality standards set by the Ministry of Health, Labour, and Welfare of Japan were tested. RESULTS: The fluoride ion concentration of the adjusted water was 0.7 mg/L and it was constant and stable. The adjusted water conformed to the water quality standard values of the Japanese Water Supply Law. CONCLUSION: Water produced with small-scale water fluoridation equipment had a fluoride concentration of 0.7 mg/L, which is the recommended concentration for caries prevention. The fluoride concentration was stable.