 Children with CHD are at high risk of developing caries Stecksén-Blicks C et al 2004. In Swedish high-risk areas for developing caries, 12 of three-year-old children had moderate and severe carious lesions ICDAS II 3-6 and 11 initial carious lesions ICDAS II 1-2 Anderson et al 2016. Based on the assumption that 10 in the intervention group and 30 in the control group will develop caries ICDAS II 1-6, p0.05 and power 0.80, a sample size of at least 65 individuals in each age group is required. 1.7.2017-31.12.2020 198 Finnish speaking families will be offered to participate in the study. To secure an even distribution block randomization will be used. The patients will be randomized into blocks of 4 and 8, with the help of Pandis et al 2011. 