OBJECTIVES: To study preventive care provided to young adults in relation to their estimated risk category over a 3-year period. METHODS: The amount and type of preventive treatment during 3 years was extracted from the digital dental records of 982 patients attending eight public dental clinics. The baseline caries risk assessment was carried out by the patient's regular team in four classes according to a predetermined model, and the team was responsible for all treatment decisions. Based on the variables 'oral health information', 'additional fluoride' and 'professional tooth cleaning', a cumulative score was constructed and dichotomized to 'basic prevention' and 'additional prevention'. RESULTS: More additional preventive care was provided to the patients in the 'low-risk' and 'some risk' categories than to those classified as 'high' or 'very high' risk (OR = 2.0, 95% CI 1.4-3.0; P < 0.05). Professional tooth cleaning and additional fluorides were most frequently employed in the 'low-risk' and 'some risk' categories, respectively. Around 15% of the patients in the high-risk categories did not receive additional preventive measures over the 3-year period. There was an insignificant tendency that patients with additional prevention developed less caries than those that received basic prevention in all risk categories except for the 'very high-risk' group. CONCLUSION: The caries risk assessment process was not accompanied by a corresponding targeted individual preventive care in a cohort of young adults attending public dental service. Further research is needed how to reach those with the greatest need of primary and secondary prevention.