Caries in primary dentition related to age, sex, social status, and county of residence in Finland.

The study material consisted of 1417 children 6-8 years old representing 86% of a stratified random sample from the Finnish population. Data on caries and social class were obtained by questionnaire from the municipal dental clinics in 1978. Clinical findings for primary teeth were recorded by local dentists. Incisors were excluded from the study. 80% of the children had caries lesions, and 63% were in need of restorative care. Mean dmft value was 4.4 mean dt, ft, and mt values were 2.3, 2.6 and 0.3, respectively. Occurrence of untreated caries lesions did not vary according to age. Compared to the girls, boys had lost twice as many teeth due to caries. No other differences were observed between sexes. Both past caries experience and need of restorative care increased continuously from the highest social class to the lowest. Observed regional differences were explained mainly by variation in social stratification, except in an area with abundant natural fluoride. More active dental care is needed for children with primary teeth, especially in lower social class.