Water fluoridation offers “modest benefits” to children’s oral health

A new study by UK scientists suggests the benefits of water fluoridation on children’s oral health are smaller than previously thought.

Wading into highly controversial territory, the research team from the University of Manchester found that adding fluoride to water supplies offers only a modest benefit to the dental health of children.

Water fluoridation still a cost effective method

Despite their findings, the scientists said water fluoridation can be seen as a cost-effective way to help reduce some of the £1.7bn (US$2bn) a year the National Health Service (NHS), one of UK’s public healthcare systems, spends on dental caries.

The team added that fluoridation should be considered alongside other measures to protect children’s dental health, particularly those from disadvantaged groups who are more likely to experience tooth decay.

“While water fluoridation is likely to be cost-effective and has demonstrated an improvement in oral health, it should be carefully considered along with other options, particularly as the disease becomes concentrated in particular groups,” said Dr Michaela Goodwin, from the University of Manchester and senior investigator on the project.

“Decayed teeth are painful and can impact on sleep patterns, learning, attention, and many aspects of general health.”

With or without fluoridation

The study tracked the oral development of nearly 3,000 children in Cumbria over a six-year period.

The children were divided into two batches across two locations: West Cumbria, where water fluoridation was reintroduced in 2013; and in the rest of Cumbria, where the water supplies are not fluoridated.

The younger cohort in West Cumbria, comprising of those born after water fluoridation was introduced, were considered to have received the full measure of effects of fluoridated water.

The older cohort was aged around five when fluoride was reintroduced into the water supply, which meant the fluoridation benefits only extend to those teeth already present in the mouth.

Modest reduction in incidence of caries

Results of the blind study showed that, in the younger cohort, 17.4 per cent of the children in fluoridated areas had decayed, filled or missing milk teeth, compared with 21.4 per cent for children in the same age group in non-fluoridated areas.

According to the researchers, this represents a modest four-percentage point reduction in the incidence of caries.

An even smaller disparity was found in the older cohort, where 19.1 per cent of the children in fluoridated areas had decayed, filled or missing permanent teeth, compared with 21.9 per cent for children in non-fluoridated areas.

“Tooth decay is a non-trivial disease, which is why measures to tackle it are so important,” Dr Goodwin added.

“The extraction of children’s teeth under general anaesthetic is risky to the child and is the most common reason for children between the ages of five and nine to have a general anaesthetic.”

More questions remain

Although tooth decay in children has dropped significantly over the last 50 years, recent data revealed around that 23 per cent of five-year-olds in 2019 has had dental decay.

“Decayed teeth are painful and can impact on sleep patterns, learning, attention, and many aspects of general health.

“But more questions remain and we hope to follow up on these children in the long term.”

The findings of this study, funded by the National Institute for Health and Care Research, were published in the journal Public Health Research.