Sept. 1, 2021

Calgary children’s dental health getting worse without community water fluoridation

Grade two students in Calgary significantly more likely to have cavities than children in Edmonton, where water is fluoridated

Calgary, ABCalgary children have been without fluoride in their drinking water since 2011, and their dental health is suffering. The findings come from a University of Calgary study published in Community Dentistry and Oral Epidemiology that compares the dental health of children in Calgary to children in Edmonton, where the municipal water supply is fluoridated.

Of the approximately 2,600 grade two students in each city who took part in the study, 55.1 per cent of Edmonton participants had one or more cavities in their baby teeth. In comparison, the number was 64.8 per cent of Calgary children.

Our findings are quite clear — fluoridation cessation is having a negative effect on children's dental health in Calgary. This reinforces the need for universal, publicly funded prevention activities—including, but not limited to, fluoridation of drinking water.

-Dr. Lindsay McLaren, PhD, professor, Cumming School of Medicine, University of Calgary and primary study investigator

Study participants, who were well matched in the two cohorts/groups were on average seven years old. They underwent a dental exam, and their parents completed a questionnaire about dental hygiene habits, diet and socio-demographic information. Fingernail clippings, a biomarker for fluoride intake, were also collected from a smaller subset of participants.

Information was collected over several months in 2018/2019 which means the Calgary participants were born after fluoride was taken out of the water supply in Calgary. Researchers controlled for various dental health variables such as brushing and flossing, other fluoride exposure, socioeconomic status and ethno-cultural background, but the differences in cavities between Calgary and Edmonton children remained.

“Cavities can significantly affect children's health and well-being, and since Calgary stopped fluoridation, we have virtually nothing in the way of primary prevention for this almost entirely preventable problem,” says McLaren. “Cavities can be painful, and they can affect a child’s ability to concentrate and learn. They can also be serious: for children under age six in Canada, cavities are the number one reason for day surgery performed under a under general anesthetic.”

This work builds on previous studies (see here and here) that collected information on children’s dental health in Calgary and Edmonton in 2013/2014. Perhaps most concerning, McLaren says, is that the difference has widened over the five-years between studies.

This study was supported by the Canadian Institutes of Health Research.

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Kelly Johnston
Senior Communications Specialist, Media Relations

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