The caries prevalence (at dentine level) of five year olds in the control group had previously been compared with the corresponding prevalence of five year olds in the general population from the national health register "KOSTRA" (Municipality-State-Report of 2010, 2011 and 2012 in three counties in Western Norway, n = 18,974). Likewise the caries prevalence at age five years of the present intervention group were compared with the general population (Municipality-State-Report of 2013, 2014, 2015, 2016, n=26161). Possible time trends in caries epidemiology of five year olds during 2010-2016 were assessed.