We describe the results aimed at determining in the commune of preschool Penaflor, with 0.6 mg F / L, prevalence, severity of dental caries and fluoride intake on a sample of 74 children from 3 to 5 years from low socioeconomic levels. To establish the percentage of caries-free children, we used the methodology described by WHO and the severity we used the dmft index. Fluoride intake was determined by measuring in a sample of urine excretion fluoride and creatinine concentration. The percentage of caries-free children reached 43.2%. The prevalence and severity of decay was increased with...