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

Calgary children have been without fluoride in their drinking water since 2011 and their dental health is suffering, according to findings from a University of Calgary study. It 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 2 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,” says Dr. Lindsay McLaren, PhD, a professor at the Cumming School of Medicine, University of Calgary, and primary investigator of the study which was published in Community Dentistry and Oral Epidemiology.

How the study was conducted

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

Information was collected over several months in 2018 and 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, says McLaren.

Why preventing cavities in kids is important

“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 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 and 2014. Perhaps most concerning, McLaren says, is that the difference has widened over the five years between studies.