Dental fluorosis: prevalence and associated factors in 12-year-old schoolchildren in Goiânia, Goiás.

OBJECTIVE To describe the prevalence of dental fluorosis, to investigate its association with individual and contextual variables among 12-year-old schoolchildren, and to determine whether there were changes in the prevalence of this condition from 2003 to 2010. METHODS This cross-sectional study used data from an oral health survey carried out in Goiânia, Goiás, in 2010 (n = 2,075), and secondary data from the files of the local health authority. Clinical data were collected through oral examinations in public and private schools. The dependent variable was the presence of dental fluorosis, assessed using the Dean Index. The independent individual variables were sociodemographic characteristics (the child's gender and race, and the mother's level of schooling) and those related to clinical conditions (caries experience, evaluated using Decayed, Missing, and Filled teeth index; and presence of periodontal calculus and/or bleeding, evaluated using Community Periodontal Index). The contextual variables were linked to the school (type and existence of toothbrushing program) and its geographic location in the city's health districts. The Rao-Scott test was performed, and the percentage difference between the prevalences in the period from 2003 to 2010 was calculated. RESULTS The prevalence of dental fluorosis in 2010 was 18.7%, being distributed as very mild (11.2%), mild (4.4%), moderate (2.6%), and severe (0.5%). No significant association was found between prevalence of dental fluorosis and the investigated variables. The prevalence of fluorosis increased 230% from 2003 to 2010, and such difference was significant. CONCLUSIONS The prevalence of dental fluorosis was low, predominantly of the very mild degree, has increased over a 7-year period, and was not associated with the individual or contextual factors studied.