The aim of the study was to evaluate the impact of a preventive-educational programme in a group of preschool children. The study's population group comprised 58 four-year-old children, with a mean age of 4.17 +/- 0.27. Plaque index and gingival index were determined, and a dental examination was performed. The children were randomly assigned to one of two groups: experimental and control. The experimental group received the educational component of the programme which was for children, parents and teachers. The preventive programme was applied to both groups and included topical application of 1.23% acidulated fluoride phosphate, pH 3.5, every 6 months. Outcomes were measured on day 8 and after 6 and 12 months under similar conditions to those at baseline. Results showed a significant decrease in gingival index and plaque index values and no significant increase in decay in the experimental group. The control group showed a significant increase in gingival index, plaque index, and decayed surfaces.