Purpose: To evaluate the effect of preventive oral hygiene measures on the development of new carious lesions. Materials and Methods: Children regularly and irregularly attending recall appointments in a paediatric dental clinic were interviewed regarding their preventive measures performance. Newly developed carious lesions were also recorded. The files of 651 children were analysed. Results: A significant negative correlation was found between newly developed carious lesions and total number (P 0.001) and frequency (interval in months to the next dental examination) of recall appointments (P = 0.021), regular toothbrushing twice a day (P 0.0001), regular brushing in the evening (P 0.001), high fluoride concentration in toothpaste (P 0.0001) and drinking water between meals (P = 0.015), but not with regular brushing in the morning or eating more than 6 times a day. Multivariate analysis revealed three of the variables independently correlated with the development of new carious lesions: brushing regularly twice a day, concentration of fluoride in the toothpaste greater than 1100 ppm and frequency of follow-ups. Conclusions: Regular toothbrushing twice a day is of high importance for caries prevention. Fluoride concentration of > 1100 ppm in toothpaste should be recommended for children (considering the child's age) in order to maximise the fluoride protective effect. The importance of attending periodic recall appointments in order to maintain long term oral health should be emphasised. Keywords: children, compliance, DMF, floss, fluoride, recall-appointments, toothpaste