The start of caries decline and related fluoride use in Norway.

The objective was to determine the start of caries decline and to estimate the use of fluorides about this time. The material consisted of service reports from the Norwegian municipal School Dental Services (SDS) and the country-based Public Dental Service (PDS), literature reports, private sales and marketing statistics, and a national health survey. The national data for the permanent dentition demonstrated a distinct decline in the average number of filled tooth surfaces from around 1970. Counties were grouped as "early", < or = 1970, and "late", > or = 1971. The 5 "early" countries showed the decline to be evident in 1968. Several local districts reported caries reductions since 1963, following the implementation of fluoride programs. Altogether, there was a steady increase in the % of schoolchildren taking part in organized brushing or rinsing programs from 1960. In 1970, 60% of the schoolchildren regularly took part in the supervised fluoride programs. From September 1971, 0.1% fluoride dentifrices became generally available over the counter in retail stores. In 1972, 32-54% of all toothpaste delivered or sold was fluoridated. The distinct time interval between the caries decline and the availability of fluoridated toothpaste rules out the possibility of an interaction before 1971. The extensive activities with fluoride-based preventive programs in the SDS and PDS have probably been the major factors behind the decline in the late 60s/early 70s.