Caries frequency among 6-17-year-old participants of the Finnish public dental care during 1975-79

Temporal trends of caries frequency in 6-17-year-old children in Finland and its counties during 1975-79 are reported. Initially the attendance rate was 70%: during the 4-year follow-up it increased to 84%. The cross-sectional annual proportion of children needing curative treatment diminished from 80% to 67% at the age of 8 years; the changes among the 12- and 16-year-old children were 78-66% and 86-76%, respectively. The proportion of entirely caries-free children increased from 2.5% to 9.2% at the age of 8 years, only a slight increase was found in the older age groups. The mean DMFT value decreased continuously at all ages: in the 8-year-old children it decreased from 2.7% to 1.7%, in 12-year-olds from 6.7% to 5.2% and at the age of 16 from 13.4% to 11.6%. The caries scores decreased most in areas where the initial values were highest. In the county with high fluoride levels, where the initial caries scores were smallest, only slight improvement in the caries situation was found; this indicates no major change in recording of caries. Although a simultaneous improvement of the national attendance rate and the caries scores were observed, no consistent associations were found between the changes in the attendance rate and the changes in various caries indices when age and geographical area were considered in the analyses. It is concluded that the marked decrease in caries frequency is mainly due to preventive measures.