ObjectiveThe objective of the study was to systematically compare barriers/facilitators providing oral hygiene to young children and dependent older people and to generate ideas to improve the implementation of oral hygiene measures.BackgroundMany older people, like children, rely on third‐party assistance for teeth cleaning. Barriers/facilitators in providing oral care services have been described in recent works. The aim of our study was to compare these results for both groups and to increase knowledge on analogies/differences in barriers/intermediaries.MethodsWe performed a systematic review. Studies reporting on knowledge, attitudes and beliefs acting as barriers/facilitators for provision of teeth cleaning were included. Thematic analysis was used and identified themes translated to domains and constructs of the theoretical domains framework and aligned to the behaviour change wheel. Based on three published reviews in children or older people, our search (PubMed via Medline), Cochrane Central Register of Controlled Trials (CENTRAL) and Web of Science, Google Scholar, last search (21 January 2023) encompassed both populations dated from their last publication (28 February 2018). The review was registered (Prospero, CRD42021278944). For quality assessment, the Newcastle‐Ottawa Scale (NOS) was used.ResultsSeventeen articles were identified (older people (n = 8), children (n = 9)). Deficits exist for both in terms of “knowledge/skills” among caregivers, with special difficulties in children with challenging behaviour and older people. “Capability” as one of the main elements of behavioural factors that are the basis for behaviour to take place (COM‐B, Capability, Opportunity, Motivation–Behaviour) is most often mentioned for children and “opportunity” for older people.ConclusionsMost of the facilitators and barriers affecting oral care provision in children are also relevant in older people. Approaches for the development of strategies for better implementation of oral hygiene measures in older people are presented.