A 15-year series analysis of caries development related to a socioeconomic variable. A study of the year group leaving the organised dental care in Göteborg, Sweden.

In a long-term series analysis the study had the aim of detecting how the used socioeconomic variables were related to the caries status development in the year group leaving the organised dental care. The study included caries epidemiological records of individuals at the Public Dental Service of Göteborg, leaving the organised dental care during 1986-2000. The City of Göteborg was divided into four districts. One incidence and one prevalence caries index was used, each presented in two subgroups: individuals with no caries record and patients with 20% of the highest index values. The socio-economical variable was individuals 18-64 years of age, seeking employment, as a percentage of the corresponding group of all inhabitants. The registered values were divided into three time sections of five years each. In the first, the socio-economic value curves were almost horizontal, in the second they showed a considerable increasing and in the third a declining tendency. The result curves for the caries-free patient groups and for patients with 20% of the highest caries index values compared to the three socioeconomical time sector results, showed an almost horizontal level concerning the incidence index values, and for the prevalence index values an inclined curve structure to the incidence curves. The result curves for the incidence index with respect to the caries-free patient group showed an almost horizontal structure, while the prevalence curves inclined towards the incidence curves during the study period. The linear structure of these curves deviated considerably from the result curves for the socio-economic time series. No correlation existed between the socio-economic data and the studied caries index values. The need for determining the time length concerning caries index observations was discussed. It must be of special interest to maintain the dental health of the studied patient group and the individuals' relation to regular dental care, when as adults they meet the dental care economy.