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Dental fluorosis and fluoride in Willoq and Cuzco: assumptions and reality in Peru -

Background: Dental fluorosis (DF) is a dental disease characterized by visual imperfections, staining, and opacity. DF is caused by superoptimal levels of the common fluoride (F) ion in consumed water sources. Natural levels of F fluctuate wildly based upon environmental, industrial, and geologic factors. Current global DF and F predictions based on location are still largely preliminary, especially in the developing world. 
 
Objective: To assess the (DF) status of the indigenous community of Willoq and a boysâ€™ orphanage in Cuzco, both located in the Sacred Valley region of Peru; to determine the F concentration in the main sources of consumed water in these two locations and in the city of Arequipa; and to compare the F levels and DF status against previous predictions. 
 
Materials and Methods: Individuals from Willoq and Cuzco, aged 8â€“69 years were examined for DF based on the Deanâ€™s Index. In each community, n = 29 for a total of n = 58. Population statistics were represented through the calculated Community Fluorosis Index (CFI). Fluoride concentrations were measured using a F ion selective electrode following EPA method 340.2. 
 
Result: The prevalence of DF in the selected groups from Willoq and Cuzco is 7% and 29%, with CFI values of 0.03 Â± 0.13 and 0.60 Â± 1.14, respectively. Willoq and Cuzco F concentrations in the water sources were 0.285 and 0.151 mg/L, respectively, while Arequipa water had a F concentration of 0.193 mg/L. 
 
Conclusion: There is a low prevalence of DF in Willoq, which corresponds to negligible water concentrations of F. Cuzco has higher levels of DF at similarly low F concentrations, a result that suggests additional F sources are not accounted for in this analysis. Arequipaâ€™s low F concentration and the nonzero DF in Peru are contrary to the previous predictions and call attention to a need for better and more refined DF and F predictions.