Objective: To examine the degree to which children, considered to be at risk from infective endocarditis, had received professional education and preventive procedures in regard to dental health, and to evaluate the knowledge of their parents of the link between oral health and infective endocarditis. Materials and methods: Questionnaires were distributed to the families of 38 children under the care of paediatric cardiology. A short dental examination was carried out. Parents were asked if they knew why oral health was of particular importance in their child. Results: Of the children, 58% demonstrated evidence of previous or current dental disease, with 24% having had at least one filling, 13% with one or more teeth showing deficiency of enamel, and 39% with untreated dental caries. Only 79% of the children were registered with a dentist. According to Chi squared test, there was no difference in the dental health of registered and non registered children. Of the study group, 29% had received instruction in oral hygiene, 42% had received dietary advice, 13% had received advice regarding fluoride supplementation or had had fluoride professionally applied, and 8% had had fissure sealants. These percentages remained relatively low even if only registered children, or only registered children with previous or current dental disease, were considered. Only 64% of parents were aware of the link between the oral health of their children and infective endocarditis. Parents of children who were registered were more likely to be aware of this link than parents of children who were not registered. Conclusions: In spite of being registered with general dental practitioners, few children with congenital heart disease had received basic education in dental hygiene. Even children known to have had dental disease and, therefore, considered to be more vulnerable, were overlooked.