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Caries in permanent dentition and social class of children participating in public dental care in fluoridated and nonfluoridated areas.

A random sample of 7-16-year-old children (n = 2778) who visited municipal dental clinics in fluoridated and non fluoridated areas were studied. Structured questionnaires were used to collect data on social class and fluoride exposure; caries diagnoses were made by local dentists in municipal dental clinics. Children from the highest social class had the lowest caries frequency in both fluoridated and nonfluoridated areas. Differences between middle and lower class children were small. Water fluoridation had a similar effect in all social classes.