Open wide: study suggests fluoridation works

CALGARY – A published report suggests a decision by the City of Calgary in 2011 to stop adding fluoride to its water supply has had a negative impact on children’s dental health in Alberta’s largest city.

The report — published Wednesday in the journal Community Dentistry and Oral Epidemiology — shows Calgary children have more than twice as many cavities as their counterparts in Edmonton, where fluoridation continues.

Researchers have also found that Calgary kids have more health issues with their baby teeth than those in the provincial capital.

While there was a general increase in tooth decay in both cities between 2004 and 2005, and again between 2013 and 2014, the increase was greater in Calgary.

Children in Calgary have an average of nine cavities and those in Edmonton have just over four.

The study’s lead author, Dr. Lindsay McLaren at the University of Calgary, says the findings suggest there are public health benefits to fluoridation.

“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,” said McLaren.

Researchers compared the dental health of Grade 2 children in Edmonton and Calgary and looked for an increase in tooth decay on the surfaces of their teeth.

They found there was a worsening in the decay of baby teeth in Calgary children since fluoridation was stopped. The number of tooth surfaces with decay per child increased by 3.8 surfaces in Calgary, compared to an increase of 2.1 surfaces per child in Edmonton.

Scientists say the average child of this age has about 20 teeth, with four or five surfaces per tooth.

The report said several different factors could be behind the rise in tooth decay in both cities, including shifting economic conditions in Alberta, an increase in the ethnic diversity in both cities and an uptick in the consumption of unfluoridated bottled water.

Many dentists said they have seen an increase in the number of cavities in Calgary children since fluoride was removed.

“We’re seeing much more extensive dental decay in a much younger population than we had seen when fluoride was in our water,” said Dr. Leonard Smith. “The fact that our city had chosen to remove the fluoride has been one of the most anti-public health measures ever in Calgary.”

Adding fluoride to public drinking water started in the mid-1940s and is seen as a way of improving dental health at the population level. Edmonton introduced the practice in 1967, while Calgary started it in 1991.

Removing fluoride from drinking water is a debate facing many communities in North America and according to the study, more than 30 communities have decided to discontinue the practice since 2005. (CTV Calgary)