A cost-effectiveness evaluation was conducted with a randomised controlled clinical trial of caries prevention measures among 6-year-old children who were assigned to either a control group or 1 of 2 experimental groups (IPFA: 2 extra professionally-delivered fluoride applications per year, or NOCTP: a non-operative caries treatment programme, like the one that was previously carried out in Nexø, Denmark. In order to determine the cost of the prevention of 1 DMFS in comparison with the control practice information on expenses incurred was collected for 3 years. The prevention of a single DMFS – depending on whether costs of dental treatment only were taken into consideration or also other social costs – were, in the IPFA programme, 269 and 1,369 euro respectively and, in the NOCTP programme, 30 and 100 euro respectively. On the basis of these results, it can be concluded that from both a dental and cost-effective perspective the NOCTP programme produces the most favourable results. Following the NOCTP strategy – during the 3-year period – just like following the IPFA approach was, however, more expensive than the standard approach.