BACKGROUND: The UN Convention on the Rights of the Child gives all children right to the highest standard of services for treatment and rehabilitation. For children with disabilities, sedation and general anaesthesia (GA) are often indicated for dental treatment; however, accessibility to this varies. The International Classification of Functioning, Disability and Health - Child and Youth version (ICF-CY) enables a biopsychosocial description of children undergoing dental treatment. AIM: To investigate conscious sedation and GA in children with complex disabilities and manifest caries and analyse how caries, child functioning, and dental service organisation relate to dental GA (DGA), comparing Argentina, France, and Sweden using the ICF-CY. DESIGN: Quantitative, cross-sectional; data collected through structured interviews, observation, and dental records. RESULTS: Sedation and DGA were common. Children with limitations in interpersonal interactions and relationships were more likely to have had DGA (OR: 5.3, P = 0.015). Level of caries experience was strongly correlated with experience of DGA. There were significant differences between countries regarding caries prevalence, sedation, DGA, and functional and environmental factors. CONCLUSIONS: Although caries experience and child functioning are important, dental health service organisation had the most impact on the incidence of DGA, and for the use of conscious sedation, for children with complex disabilities.