Some factors associated with the caries decline among Norwegian children and adolescents: age-specific and cohort analyses.

The purpose of this study was to evaluate factors related to the caries decline in children between 1966 and 1983. The decline started in the late sixties for the 8- to 11- and the 17-year-olds, and after 1971 for the remaining age groups. Regression analyses confirmed a significantly different start of the decline. Fluorides in school-based programmes, lozenges, and toothpaste, as well as education and sale of antibiotics were significantly (p< or =0.01) related to the caries decline in partial correlation analyses. Fluoride toothpaste was only significantly related to the decline in the last part of the period of observation. Supervised fluoride rinsing and brushing programmes at school may explain most of the decline before 1971. The later decline may be related to all fluoride agents and to education. Use of fluorides and other preventive efforts aimed at pre-school children may have contributed to the continual decline in the number of fillings in the permanent teeth of the youngest cohorts.