Chances are you’ve heard of fluoride before. Fluoride is one of the most abundant elements found in nature and is a mineral found in your bones and teeth. It’s also commonly used in dentistry and in toothpaste to strengthen your enamel, the outer layer of your teeth. Many cities in Canada also add small amounts of fluoride to the water supply in a process called “water fluoridation” to make teeth stronger and more resistant to cavities. Several other benefits of fluoride include slowing down the loss of minerals from tooth enamel, reversing early signs of tooth decay, and preventing the growth of harmful oral bacteria. 
Fluoride in toothpaste is beneficial because, when you brush your teeth with fluoride toothpaste or use other dental products containing fluoride, it’s applied topically to the surface of your teeth. This is why using mouthwash with fluoride is also of benefit. Toothpaste with fluoride has been responsible for a significant drop in cavities since 1960 , and water fluoridation was once heralded as one of the best public health achievements in the twentieth century. 
Another study done from 1965 to 1985 that assessed the effects of fluoride added to salt in Colombia, Hungary, and Switzerland revealed that the number of teeth affected by caries was reduced approximately 50%.
So why, then, has it come under such controversy?
One of the arguments against fluoride is that it is possible to over consume it if it is added to our water supply. The good news is that, in Canada, the recommended levels are 0.7 ppm, or parts per million, well below the toxicity threshold. Not to mention that when you are using a fluoridated toothpaste or mouthwash, “The amount of fluoride ingested from toothpaste depends on the amount, the person’s swallowing control, and how often they use it. Estimated typical amounts of fluoride ingested daily from toothpaste are 0.1 mg to 0.25 mg for infants and children aged 0 to 5 years, 0.2 to 0.3 mg for children aged 6–12 years, and 0.1 mg for adults.” 
Too much use of fluoride can have the potential to cause something called fluorosis in children under eight. Fluorosis is a discoloration of teeth, usually presenting as white, opaque marks, lines, or mottled enamel and poor mineralization. But according to a Canadian Health Measures Survey done from 2007 to 2009, it was found that only 16% of Canadian children may have very mild or mild dental fluorosis, so few children, in fact, that it was too low to report.
According to a provincial report compiled in 2015, only 26% of Saskatchewan’s population currently has access to water with fluoridation.  Humboldt, Melfort, Moose Jaw, Prince Albert, Saskatoon, Swift Current and Weyburn account for the most significant numbers of residents in the province that have access to fluoridated water. Regina’s water is currently not fluoridated, however, there are plans to add fluoride to the water by 2025 once updates to the Buffalo Pound water treatment plant are finished.
 Saskatchewan Community Fluoride Data Report 2015