The aim of this study was to determine the need for oral health care in young Belgian children in the municipality of Leuven, Belgium. The sample consisted of 750 boys and girls (3 years = 200, 4 years = 200 and 5 years = 350). Clinical examination was carried out by one examiner and duplicate recordings were made on 10% of the sample. The clinical examination included recording of: (1) plaque index; (2) gingival index; (3) caries index; and (4) fluorosis index. Plaque and gingival indices were recorded at six sites of smooth surfaces on selected teeth. Occlusal plaque was also registered. Before the clinical examination for caries and fluorosis, the children had their teeth professionally cleaned with toothbrushes and dental floss and dried by means of gauze bandages. In all age groups, the percentage of plaque-free sites was of the order of 60% and sound gingiva was identified at 83% of the recorded sites. The percentages of caries-free children were 69% (3 years), 57% (4 years) and 52% (5 years). The mean deft scores (standard error) were 1.37 (+/- 0.21), 1.76 (+/- 0.21) and 2.03 (+/- 0.17). The corresponding mean defs scores were 2.04 (+/- 0.44), 2.46 (+/- 0.35) and 3.75 (+/- 0.42). Non-cavitated active lesions, included in the defs scores, represented about 50% of all caries lesions. Early signs of dental fluorosis were identified in 19% (3 years), 17% (4 years) and 9% (5 years) of children. The need for oral health care in the population studied is mainly related to non-operative treatment procedures aimed at controlling the progression of disease.