Background The World Health Organisation has set out a clear priority for the implementation of interventions to reduce the burden of Early Childhood Caries (ECC), a global public health problem affecting over 500 million children around the world and having a substantial impact on child well-being and health system expenditure. The aim of this study was to assess and develop international expert consensus on the evidence for fluoride-based interventions in early-year education settings (kindergartens/nursery and primary schools) for reducing ECC and to synthesise clear programme-level recommendations with regard to ECC prevention in this setting. Methods A systematic overview of systematic reviews, trials, and observational studies was performed to identify and critically appraise the available evidence on the effectiveness and cost-effectiveness of fluoride-based interventions in early-years education settings to prevent ECC. This was followed by a three-stage modified Delphi panel study (n= 21) consisting of: round 1, an online survey to gather opinions on safety, effectiveness and feasibility of interventions; round 2, an iterative survey to consider collated group opinion and gather feedback on review findings; and finally, an online workshop with presentations and facilitated in-depth, recorded group discussions. Results There was high-quality evidence and consensus on delivering supervised toothbrushing in kindergartens (nurseries) and primary/elementary schools; this is safe and cost-effective, shows greater benefit to more disadvantaged children, helps child social development, and is feasible in high and low/middle-income countries. There was more moderate support for the effectiveness and cost-effectiveness of fluoride varnish application in this setting (especially where supervised toothbrushing with fluoride is in place). It was agreed that policy makers should prioritise at-risk groups where resources are limited, and that systemic fluoride interventions (Fluoride tablets, drops, milk, and salt) in this setting are no longer a priority.  Conclusion Supervised toothbrushing with fluoridated toothpaste is the most effective, cost-effective, feasible and safest mechanism for children in early education settings. Universal coverage is preferred but where resources are limited targeting based on need is indicated. Panel consensus is that it remains appropriate in water fluoridated areas and is largely feasible in low/middle-income countries.

The authors have declared no competing interest.

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