The caries prevalence in patients with cleft lip and/or palate is higher in both the deciduous and permanent dentition, compared to non-cleft patients. Inadequate oral hygiene is one of the main causes. Additional, individualized advice concerning diet and oral hygiene, such as the additional advice of the Ivoren Kruis (Dutch association of dental hygienists), is of great importance. During curative treatment, attention should be paid to any dental anxiety and possible reduced compliance.