Water fluoridation, supported by the Brazilian Oral Health Policy, has been a challenge as a public measure to protect Oral Health, due to some current insufficiencies in public management for the implantation of this measure in most Brazilian cities. The present study aimed to monitor, the levels of fluoride in drinking water in Nova Friburgo - RJ-Brazil (NF), on a regular and a systematic manner for a 12 months period, as an external control measurement performed by a public university. Water samples were collected, in duplicate, from 26 localities throughout the city, on a monthly basis, on randomly established dates. The fluoride concentration in the water samples was measured by using an ion-specific electrode coupled to a potentiometer, according to standards supplied by Cecol/USP(2011). Data showed a large variation of fluoride concentration in water samples, ranging from minimum 0.00 ppmF and maximum 0.98 ppmF, with few samples into the interval between 0.65 and 0.94 ppmF, which had the best benefit to prevent dental caries. Fluoride concentration in public water in this city can be considered under the minimum required levels in most of the evaluated samples, even in those from the Water Treatment System (WTS), which has water fluoridation. Thus, water fluoridation and its external control should be established on a regular basis in Nova Friburgo-RJ, Brazil because they are relevant public measures to promote oral health.
