SOURCE: University of Calgary

University of Calgary

February 17, 2016 10:30 ET

Impact of fluoridation cessation seen in Calgary children: Study

CALGARY, AB --(Marketwired - February 17, 2016) - A newly published study compared Grade 2 students in both Edmonton and Calgary, and found that fluoride cessation in Calgary has had a negative impact on children's health.

In primary teeth, known more commonly as baby teeth, there was a worsening in tooth decay in Calgary since the discontinuation of fluoridation in 2011, as compared to Edmonton, where water is still fluoridated. In fact, the number of tooth surfaces with decay per child increased by 3.8 surfaces in Calgary during the time frame of the study, as compared to only 2.1 in Edmonton. This is a statistically significant difference. The average child has about 20 teeth with four or five surfaces per tooth.

"This study points to the conclusion that tooth decay has worsened following removal of fluoride from drinking water, especially in primary teeth, and it will be important to continue monitoring these trends," says Lindsay McLaren, PhD, from the University of Calgary's Cumming School of Medicine and O'Brien Institute for Public Health, the study's lead author. 

Tooth decay is the most common infectious disease in children. The consequences of tooth decay include pain for the child, expense of dental treatments such as extractions and fillings, and the soreness can also influence the performance of a child at school. Dental concerns are also the leading cause of day surgery for young children in Canada, including in Alberta.

"The early effects of fluoridation cessation found in this study support the role of water fluoridation in contributing to improved oral health of children and that it is a public health measure worth maintaining," says Steven Patterson, dentist, Professor at School of Dentistry, University of Alberta.

McLaren carried out the study with a number of colleagues from the University of Alberta and Alberta Health Services. 

"I was not at all sure that we would see these effects. It had only been about three years since fluoride was removed, which is on the short side; plus, there are potentially several sources of fluoride in both environments, which would tend to reduce the observed effect of removing fluoride from the drinking water," says McLaren who is an associate professor in the department of Community Health Sciences.

Researchers used surveillance data from students that was collected in 2004/05 and compared it to data they collected from students in the 2013-2014 school years in both cities. Grade 2 students were picked because they are at an age where researchers could examine both baby teeth and adult teeth in one group. Data was collected from more than 5,000 children in the two cities -- the schools were randomly selected from both the public and Catholic school systems. The two cities were compared because Edmonton has had fluoride since 1967 and still does, while Calgary stopped the practice of community water fluoridation in 2011 (which had been in place only since 1991).

Removing fluoride from drinking water is a debate facing many communities in North America and around the world. Fluoride is a tooth-enamel-strengthening mineral that was first introduced into public drinking water in 1945.

There are currently few published studies that look at the effects of fluoridation cessation. Researchers from the paper hope their study can be explored by decision makers who are involved in these discussions. 

The results of the study were published in the February issue of Community Dentistry and Oral Epidemiology.

The study was funded by Alberta Health, the Canadian Institutes of Health Research (CIHR), and Alberta Health Services. 

Lindsay McLaren is supported by CIHR (Institute of Population & Public Health and Institute of Musculoskeletal Health & Arthritis), the Public Health Agency of Canada, and Alberta Innovates -- Health Solutions.

About the University of Calgary
The University of Calgary is making tremendous progress on its journey to become one of Canada's top five research universities, where research and innovative teaching go hand in hand, and where we fully engage the communities we both serve and lead. This strategy is called Eyes High, inspired by the university's Gaelic motto, which translates as 'I will lift up my eyes.'

For more information, visit Stay up to date with University of Calgary news headlines on Twitter @UCalgary. For details on faculties and how to reach experts go to our media centre at

About the Cumming School of Medicine
The University of Calgary's Cumming School of Medicine is a leader in health research, with an international reputation for excellence and innovation in health care research and education. We train the next generation of health practitioners, and take new treatments and diagnostic techniques from the laboratory to the patient, always keeping in mind our goal: Creating the Future of Health.

The medical school was created in 1967 and on June 17, 2014, was formally named the Cumming School of Medicine in recognition of Geoffrey Cumming's generous gift to the university.

For more information, visit, or follow us on Twitter@UCalgaryMed.

About the O'Brien Institute for Public Health
With more than 400 members, the University of Calgary's O'Brien Institute for Public Health is a virtual, interdisciplinary network integrating research groups, academics, health professionals, community leaders, and policy makers across the health continuum to catalyze excellence in population health and health services research. Together, O'Brien Institute members strive to produce new knowledge and evidence to inform, and help shape, public health agencies and health systems for the benefit of local, national and global communities - achieving the institute's vision of Better Health and Health Care.

Image Available:

Contact Information

  • Media Contact:

    Marta Cyperling
    Media Relations Manager, Cumming School of Medicine
    University of Calgary