Availability of data and materials The datasets used and analysed during the current study are available from the corresponding author on request. Notes adjusted to EU19 prices (5). The probability of receiving an amalgam given that you received an extraction at your previous visit is of course zero. Abbreviations CWF: Community water fluoridation PWS: Public water supply EPA: Environmental Protection Agency Ireland WTS: Wate

Abstract

Background

Community water fluoridation (CWF), the controlled addition of fluoride to the water supply for the prevention of dental caries (tooth decay), is considered a safe and effective public health intervention. The Republic of Ireland (Ireland) is the only country in Europe with a legislative mandate for the fluoridation of the public water supply, a key component of its oral health policy. However, more recently, there has been an increase in public concern around the relevance of the intervention given the current environment of multiple fluoride sources and a reported increase in the prevalence of enamel fluorosis. The aim of this economic analysis is to provide evidence to inform policy decisions on whether the continued public investment in community water fluoridation remains justified under these altered circumstances.

Methods

Following traditional methods of economic evaluation and using epidemiological data from a representative sample of 5-, 8-, and 12-year-old schoolchildren, this cost-effectiveness analysis, conducted from the health-payer perspective, compared the incremental costs and consequences associated with the CWF intervention to no intervention for schoolchildren living in Ireland in 2017. A probabilistic model was developed to simulate the potential lifetime treatment savings associated with the schoolchildren’s exposure to the intervention for one year.

Results

In 2017, approximately 71% of people living in Ireland had access to a publicly provided fluoridated water supply at an average per capita cost to the state of €2.15. The total cost of CWF provision to 5-, 8-, and 12-year-old schoolchildren (n?=?148,910) was estimated at €320,664, and the incremental cost per decayed, missing, or filled tooth (d3vcmft/D3vcMFT) prevented was calculated at €14.09. The potential annual lifetime treatment savings associated with caries prevented for this cohort was estimated at €2.95 million. When the potential treatment savings were included in the analysis, the incremental cost per d3vcmft/D3vcMFT prevented was -€115.67, representing a cost-saving to the health-payer and a positive return on investment. The results of the analysis were robust to both deterministic and probability sensitivity analyses.

Conclusion

Despite current access to numerous fluoride sources and a reported increase in the prevalence of enamel fluorosis, CWF remains a cost-effective public health intervention for Irish schoolchildren.

Peer Review reports

Availability of data and materials

The datasets used and analysed during the current study are available from the corresponding author on request.

Notes

  1. adjusted to EU19 prices (5).
  2. The probability of receiving an amalgam given that you received an extraction at your previous visit is of course zero.

Abbreviations

CWF: Community water fluoridation
PWS: Public water supply
EPA: Environmental Protection Agency Ireland
WTS: Water treatment scheme
HSE: Health Service Executive
FACCT study: Fluoride and Caring for Children’s Teeth
O&M: Operating and maintenance
H2SiF6 : Hydrofluosilicic acid
d3vcmft/D3vcMFT: Decayed, missing or filled teeth recorded at the dentine level, with or without cavitation
PSA: Probabilistic sensitivity analysis

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Acknowledgements

The authors would like to thank all the contributors to the FACCT study, the Irish Expert Body on Fluorides and Health, the Health Service Executive, the Environmental Protection Agency Ireland, Irish Water and Tobin Consulting Engineers.

Funding

This economic evaluation of community water fluoridation was undertaken as part of the Health Research Board awarded grant CARG (Collaborative Applied Research Grant)/2012/34, which also included the FACCT (Fluoride and Caring for Children’s Teeth) Study. The HRB funded this research but had no role in the design, data collection, interpretation of data or writing of this manuscript.

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