AIM: To estimate the prevalence of malocclusion, dental injuries and dental anomalies in a sample of 3-5-year-old Belgian children. DESIGN: A cross-sectional study of 3-5-year-olds attending kindergartens in the municipality of Leuven, Belgium. METHODS: A total of 750 boys and girls participated in the study. The children were examined at the University School Health Centre in connection with their obligatory medical check-up. The clinical examination was performed by one examiner using generally accepted criteria for these oral conditions. RESULTS: 10.1% of the examined children had posterior cross-bite whereas over-bite was seen in only 2.0% of the sample. Open-bite was detected in 32.0% of the studied population. Boys showed a tendency for a higher frequency of malocclusions than girls. Traumatic injuries were identified in 18.0% of children. These were almost entirely restricted to maxillary incisors. Crown fractures were responsible for 42% of all injuries. The following dental anomalies were seen: six cases of supernumerary teeth, three cases of hypodontia, five cases of double teeth and one case of conical maxillary lateral incisor. CONCLUSION: Our findings emphasize the importance of early detection of these oral conditions in order to permit effective and long-term planning, according to the child's individual requirements.