This investigation studied the dental health status of a group of 184 Australian Aboriginal children with a mean age of 4.4 +/- 0.8 years, who were attending pre-schools in metropolitan Brisbane, a non-fluoridated state capital city. The DDE (Developmental Defects of Enamel) Index was used to chart enamel hypoplasia and enamel opacities. WHO criteria was used to diagnose dental caries. The results showed that 98% of children had at least one tooth showing developmental enamel defects. Each child had a mean of 3.8 +/- 1.7 teeth affected by enamel hypoplasia and another 1.1 +/- 0.8 teeth affected by enamel opacity. Seventy-eight percent of the children had dental caries. The mean number of decayed, missing, filled teeth (dmft) per child was 3.8 +/- 3.7. The decayed component constituted 3.5 (95%) of the mean dmft, indicating a high unmet restorative need in this group. The mean dmfs (decayed, missing, filled, surfaces) was 5.9 +/- 7.3. Maxillary anterior labial decay of at least one tooth affected 43 (23%) of the children. In this sub-group, the dmft and dmfs was 9.1 +/- 2.8 and 15.4 +/- 7.7 respectively. Oral debris was found in 98% of the children. It is hypothesized that the high levels of underlying developmental enamel defects, compounded by low fluoride exposure, poor oral hygiene and a diet high in refined sugars pose an important caries risk factor in this group of children.

A number of reports during recent years have suggested that dental caries is decreasing in several populations. In order to substantiate this, recordings of dental caries collected over a 10-year period were analyzed. All children received systematic preventive and restorative care from kindergarten to 9th or 10th grade (age approximately 16 years). Each cohort consisted of 50-60 children, and data on dental caries were available on all children in 1st through 7th grade over a 9-year period. Mean DMFS had decreased with 72% for 1st graders, 65% for 4th graders and 69% for 7th graders. Analyses of the distribution of children according to DMFS showed that in spite of the general decrease in mean DMFS, some children still showed high DMFS-values. The variability according to DMFS was increased during the same period as indicated by the coefficient of variation. Furthermore, children with a given, high DMFS account for a decreasing fraction of all DMF-surfaces in the population as the mean DMFS decreases. It is suggested that the effect on mean DMFS for the entire group of children of a hypothetical, individualized preventive program for high-risk individuals would be limited. In the light of these findings the appropriateness of special preventive programs for "high-risk" individuals is questioned.

This investigation was carried out in order to collect information regarding oral health in a group of schoolchildren in Kandy, Sri Lanka. 614 children of 6.9, 12 and 15 years were selected by stratified random sampling and examined under field conditions. The primary dentition showed a high rate of caries on all types of surfaces. Caries in the permanent dentition was mainly located to pits and fissures below the age of 12 years, after which smooth surface caries developed. The D-component was by far the largest component of the DMF-index in both the primary and the permanent dentition. The results are discussed in the light of the existing dental care delivery system in Sri Lanka.