The Sapere Research Group (Sapere) has evaluated the benefits and costs of water fluoridation in New Zealand.
Sapere’s review finds that oral health is a major issue in New Zealand. Dental decay accounts for approximately 1% of all health loss in New Zealand due to early death, illness or disability.
The review also finds strong evidence for benefits of water fluoridation. A large body of epidemiological evidence over 60 years confirms water fluoridation prevents and reduces dental decay:
- children and adolescents: 40% lower lifetime incidence of dental decay on average
- up to 4 years: 48% reduction in hospital admissions for treatment of tooth decay
- 18 to 44 years: 21% reduction in dental decay
- 45 years and over: 30% reduction in dental decay.
Sapere estimates that adding fluoride to New Zealand’s water treatment plants supplying populations over 5000 is cost-saving; and for those water treatment plants supplying populations over 500, it is likely to be cost-saving. The net discounted saving over 20 years is estimated to be $1,401 million, made up of a cost of fluoridation of $177 million and cost offsets of $1,578 million from reduced dental decay. Sapere estimates the 20-year discounted net saving of water fluoridation to be $334 per person, made up of $42 for the cost of fluoridation and $376 savings in reduced dental care.
Sapere also estimates the provision of fluoridated water to all of New Zealand reticulated water supplies over 20 years would result in between 8800 and 13,700 quality adjusted life years (QALYs) gained.
Equally important is strong evidence water fluoridation reduces dental decay regardless of ethnicity, socioeconomic status and age. Because of the increased amount of dental decay among Maori and those who are most deprived, Sapere expects these groups to have a greater absolute benefit from water fluoridation.
A follow-up report which provides a DHB-level evaluation of the benefits and costs of water fluoridation is now available: The benefits and costs of water fluoridation - a summary for DHBs.