Prevalence and severity of dental caries in adolescents aged 12 and 15 living in communities with various fluoride concentrations

Objectives: To determine the experience, prevalence, and severity of dental caries in adolescents naturally exposed to various fluoride concentrations. Methods: A cross-sectional census was conducted on 1,538 adolescents aged 12 and 15 years living at high altitude above sea level (>2,000 m or > 6,560 ft) in above-optimal fluoridated communities (levels ranging from 1.38 to 3.07 ppm) of Hidalgo, Mexico. Sociodemographic and socioeconomic data were collected using questionnaires. Two previously trained and standardized examiners performed the dental exams. Results: Caries prevalence was 48.6 percent and mean of decay, missing, and filling teeth (DMFT) for the whole population was 1.15 +/- 1.17. In terms of severity, 9.6 percent of the adolescents had DMFT >= 4, and 1.7 percent had >= 7. The significant caries index (SiC) was 2.41 in the group of 12-year-olds, and 3.46 in the 15-year-olds. Higher experience and prevalence were observed in girls, in children with dental visit in the past year, those in the wealthiest socioeconomic status (SES) (quartiles 2, 3, and 4), those whose locale of residence is in San Marcos and Tula Centro, and in fluorosis-free children and those with moderate/severe fluorosis. In an analysis of caries severity (DMFT >= 4), both adolescents with very mild/mild and moderate/severe dental fluorosis have higher caries severity. Conclusions: The results indicated that caries experience, prevalence, and severity as well as SiC index among 12- and 15-year-old adolescents were relatively low Sociodemographic and socioeconomic variables commonly associated with dental caries were also observed in Mexican adolescents. Unlike other studies, we found that caries increased with higher SES. Fluoride exposure (measured through fluorosis presence) does not appear to be reducing the caries prevalence (DMFT > 0) or caries severity (DMFT > 4) in these high-altitude communities.