Community water fluoridation (CWF) is a safe, efficient, and inexpensive way to reduce dental cavities (also called tooth decay or dental caries) in adults and children, yet currently only 39.8% of Canadians receive fluoridated drinking water, down from 42.6% in 2007.1 However, this rate mostly captures CWF in larger cities, as it is less common in smaller communities and in Indigenous populations. Severe cavities and tooth loss are more common among Indigenous peoples, new Canadians, and people living in poverty.2,3 While oral health is not traditionally part of the work of family physicians, the link between oral health and overall health is well documented, so family physicians have a responsibility to care about it. The CanMEDS–Family Medicine 2017 competency framework states that family physicians should be health advocates, meaning they should use their expertise and knowledge to improve the health of their patients and communities.4 Family physicians should collaborate with oral health care providers, local health advocates, and elected officials to ensure all Canadians have access to fluoridated water.
Fluoridation of drinking water was introduced in Brantford, Ont, in 1945. Comparisons of water in Brantford and in other communities were part of the initial evidence that established CWF effectiveness and led to the US Centers for Disease Control and Prevention naming it 1 of the 10 greatest public health achievements of the 20th century.5 From 1945 on, municipalities began to fluoridate, but from the very beginning fluoridation opponents used every conceivable argument—emotional and political—to prevent its adoption6,7 or to stop it.1 As water treatment decisions across Canada lie within municipal jurisdictions, debate occurs at the local level, but municipal officials often lack the training needed to appraise science and evidence. They are susceptible to strong views of influential community members and vitriolic campaigns against public health.7 This history has produced uneven adoption of CWF across the country. Ontario now has the highest CWF rate, with 73.2% of the population on community water systems receiving fluoridated water, but less than 2% receiving it in British Columbia, Yukon, Quebec, New Brunswick, and Newfoundland and Labrador (Table 1).1 In Australia, fluoridated water is supplied to more than 90% of the population in all but 1 state.8 Why not in Canada?
Water fluoridation rate estimates in Canadian jurisdictions: Data are mainly from 2021.
As health advocates, we must promote water fluoridation and refute arguments against it. There are 4 aspects of CWF that are often poorly understood: the importance of dental health, CWF effectiveness, CWF safety, and CWF ethics and legality.
Dental disease and health
Fluoridation opponents may not appreciate the frequency and severity of dental disease and its harm to general health. Among children 6 to 11 years old, 57% have dental caries, with a mean of 2 filled deciduous teeth. This percentage rises with age (Table 2).2 Dental treatment is the most common reason children receive general anesthesia in Canada, representing 31% of all day surgeries among children younger than 6 years.9 People of all ages with untreated dental caries can develop periodontal disease, abscesses, cervical fascial infection, and chronic pain. People with dental pain find it difficult to chew, and pain disturbs sleep, interrupts learning, and affects mood.10 Those with missing or decayed teeth often feel self-conscious and are unwilling to smile. They are less likely to obtain client-facing jobs, possibly earning lower incomes,6 and may go into debt to pay for urgent dental treatment.10
Prevalence of dental decay in Canada
Dental disease is costly and cumulates over time. A small filling (restoration) given to a child on a single surface costs approximately $150.11 Young children or those with disabilities may require general anesthesia for dental work, increasing the cost of the procedure. A dental cavity, once treated, inevitably leads to a cascade of further treatments (Box 1).11 Dental costs can become a “tax” on disadvantaged individuals, especially those living in rural areas where access to dental services is limited.6 The new Canada Dental Benefit covers only up to $650 per year for some children younger than 12.12
Costly natural history of a childhood filling
A single small filling (restoration) is usually the beginning of a lifelong saga of interventions, discomfort, and cost. Even 1 filling is an indicator of potential poor mouth care and dental hygiene: those with 1 filling are likely to need several more in future. Children who have undergone extensive treatment at a young age are at a higher risk of recurrent decay and retreatment.
If a child is uncooperative at a dental appointment, they might be referred to a pediatric dentist for conscious sedation, resulting in a more expensive procedure. For young children or those with disabilities making them unable to cooperate, dental work must be conducted under general anesthesia; the costs of this treatment must be borne by the parents if they do not have adequate dental coverage
An initial filling (restoration) of a small cavity costs about $150.11 If it is properly cared for, an amalgam (silver) filling will last 10 to 15 years before needing a replacement. If it is in a visible area, or if parents fear mercury poisoning from the amalgam, a white composite filling may be used, but they generally deteriorate faster, lasting only 7 to 10 years
Each time a filling is replaced, the cavity is “freshened” and enlarged by removing more tooth structure, increasing costs ($370 for a large filling).11 Over time, the tooth structure weakens and may crack. Infection may track down the root, leading to root canal treatment ($700 to $1500). Crowns ($1500) or bridges ($4500) may be needed. When there is more severe damage, the tooth must be extracted and perhaps replaced with a dental implant
Multiple tooth loss could eventually lead to partial or complete dentures, which becomes an additional bother and expense
Effectiveness of water fluoridation
Some opponents claim that fluoridation is ineffective. They cite a Cochrane review that criticized the quality of evidence for fluoridation because of study design and risk of bias.13 Nonetheless, those authors concluded that CWF is 22% effective in reducing cavities. Randomized controlled studies are impossible to perform with large samples over the many years needed to demonstrate effects, so we must be content with parallel cohorts of communities.
Detailed evidence reviews conducted by authoritative groups in Canada,14 Australia,8 New Zealand,15 and Ireland16 used current best methods and reached similar conclusions that fluoridation effectively reduces dental decay by around 25% (Appendix 1, available from CFPlus*).
Children growing up in areas with fluoridated water have better dental health than those without. At all ages, tooth decay is reduced by about 25% and the proportion of children with no decay in either deciduous or permanent teeth is about 15% higher than those in unfluoridated areas. Recently, studies on fluoridation cessation in Calgary, Alta,17,18 and in Juneau, Alaska,19 have demonstrated that dental health of schoolchildren deteriorates after water fluoridation stops, even in this era of fluoridated toothpaste and other measures.
Since dental treatment is expensive, fluoridation is cost-effective, with savings estimated at more than 30 to 40 times the cost of supply over a 20-year period in large water systems—less in smaller ones.20 It has been difficult for small municipalities to obtain cost-effective systems, but newly developed equipment makes this easier to achieve.21 The cost is borne by public water supply authorities, while gains accrue to families in the form of dental work not needed. Such gains are difficult to measure and, like other preventive actions, seldom appreciated.
Fluoridation safety
Opponents misstate fluoridation safety. They often focus on the toxicity of elemental fluoride and some of its compounds. At the Canadian standard of 0.7 mg/L (0.7 ppm with maximum allowable concentration of 1.5 mg/L)22 fluoride is not toxic. Water system operators must control fluoridation systems carefully to stabilize this concentration.
Opponents raise concerns about dental fluorosis and the possibility of affecting brain development. Fluorosis is discolouration and pitting of teeth that occurs among those with higher fluoride intake, but in Canada moderate or severe fluorosis is too rare to allow reporting.2 Such discolouration appears likely related to childhood ingestion of either excess fluoridated toothpaste or well water with high fluoride levels. Since toothpaste in Canada contains up to 1150 ppm of fluoride,23 parents must monitor children younger than 8 years to prevent its overuse, regardless of whether the water is being fluoridated (Box 2).24,25
Tooth care guidelines for children: Additional sources are provided for assistance with child tooth care.
Risk assessment tool
The Canadian Caries Risk Assessment Tool assesses the dental risk of children younger than 6 years of age: https://umanitoba.ca/CRA_Tool_ENG_Version.pdf
- The tool provides photos of tooth lesions and a checklist of risk factors. If the child scores as high risk, apply fluoride varnish and refer for dental assessment and care
- The assessment tool can also be found on the Rourke Baby Record website: https://www.rourkebabyrecord.ca/downloads
Toothbrushing advice
A responsible adult should brush the child’s teeth twice daily for 2 minutes from eruption until the child is able to do so effectively themselves, usually around 8 to 9 years.24 This includes using the right amount of fluoridated toothpaste. The Winnipeg Regional Health Authority provides helpful tips: https://wrha.mb.ca/wp-content/site-documents/healthinfo/preventill/files/ECTD_ToothbrushTips.pdf
Proper use of fluoridated toothpaste
Health Canada provides a toothpaste guide for children25: https://www.canada.ca/en/health-canada/services/healthy-living/your-health/environment/fluorides-human-health.html#s5
Amount of toothpaste
Guidelines for toothpaste amount:
First tooth appearance to 3 years of age: apply a smearof toothpaste the size of a grain of rice25
From 3 to 6 years: apply a green pea–sized amount25
From 6 to 9 years: apply a green pea–sized amount and supervise and assist child with toothbrushing
From 9 years to adult: ensure teeth are being brushed regularly for at least 2 minutes and a green pea–sized amount of toothpaste is being used
It is best for the toothpaste to remain in contact with the teeth after brushing: excess should be spat out, but it is not advisable to rinse the mouth with water.24 Health Canada has additional guidance on cleaning a child’s mouth24: https://www.canada.ca/en/public-health/topics/oral-health/caring-your-teeth-mouth/children.html#a4.
Recently, researchers at York University in Toronto, Ont, asserted that even the concentration in fluoridated water causes reduced intellectual achievement in children born in those areas.26 Yet, fluoridation has more than 75 years of safety evidence; IQ changes in countries or areas where CWF started or ceased have not been observed. The assertion that fluoridation causes decreased intelligence is an extraordinary claim requiring extraordinary evidence. Moreover, the Canadian Agency for Drugs and Technologies in Health appraised the York University paper and noted that the main effect (which was reported on only 1 line of table 1) showed no difference in IQ between those living in areas with CWF and those without.27 Other studies and organizations have concluded that fluoridation has no effect on neurologic development.8,15,28
Ethics and law regarding fluoridation
Is it ethical to fluoridate? Fluoride is a mineral that is added as a supplement, similar to the addition of iodine in salt, folate in flour, and iron in breakfast cereals. Opponents claim fluoride is a “medication” and it is unethical to medicate anyone against their will. After exhaustive consideration of the arguments and evidence, the Canadian Agency for Drugs and Technologies in Health concluded that CWF can be “ethically justified because the balance of its public health benefits outweigh its measured harms, and are significant enough to override the concerns related to individual choice.”29
Some assert it is illegal to “force” people to accept fluoridated water. In 2004 the British Columbia Court of Appeal ruled that when a democratic majority votes in favour of CWF, a litigant cannot halt the public health measure because of concerns about the rare incidence of severe fluorosis.30 The overall benefit for most community members may prevail over a few objectors. In this case, the major reduction in tooth decay was more important than concerns about the possibility of cosmetic changes of fluorosis. The Supreme Court of Canada did not grant an appeal and might be understood to have expressed disapproval of the request by dismissing it with costs.31
Next steps for family physicians
Overwhelming evidence has led authorities around the world to conclude that CWF is effective and safe. Fluoridation improves dental and general health, more so for children who are disadvantaged because adherence to mouth care routines is low. Consequently, family physicians should strongly encourage patients to use fluoridated toothpaste according to guidelines (Box 2)24,25 and should work to ensure that patients have fluoride in their drinking water.
In communities without CWF, or if the question of ceasing fluoridation arises, speak with municipal elected officials to understand their views. Learn their perceptions of the costs and complexity of fluoridation, and whether they support CWF. They might respond positively to information from authoritative sources. Other officials might have misinformed views stemming from antiscience or conspiracy ideas, possibly influenced by the vitriolic antifluoride campaigners on social media and email who use the Gish gallop approach32 to swamp rational appraisal of evidence. Depending on your community’s situation, you may develop an alliance with a variety of local experts and activists to mount a campaign, as we did in Calgary, after the city council voted in 2011 to overturn the results of 2 plebiscites in favour, thereby ceasing water fluoridation. In 2021 the “Fluoride Yes!” campaign33 (Figure 1) won a plebiscite with 62% voter support34; the new council immediately voted to reinstate fluoridation. As a result of the campaign, the Canadian Fluoridation Society (https://canadianfluoridationsociety.ca/) was formed and is ready to assist not only family physicians with CWF advocacy, but anyone in Canada.
Fluoride Yes! campaign button
Notes
Suggested reading
Society of Teachers of Family Medicine Group on Oral Health. Smiles for Life: a national oral health curriculum [website]. Smiles for Life Oral Health; 2023. Available from: https://www.smilesforlifeoralhealth.org/. Accessed 2023 Apr 6.
Smarsh S. Poor teeth [essay]. Aeon Media Group Ltd; 2014. Available from: https://aeon.co/essays/there-is-no-shame-worse-than-poor-teeth-in-a-rich-world. Accessed 2023 Apr 6.
Videos—fluoride. Wellington, NZ: New Zealand Ministry of Health; 2023. Available from: https://www.health.govt.nz/your-health/healthy-living/teeth-and-gums/fluoride/fluoride-facts/videos-fluoride. Accessed 2023 Apr 6.
Footnotes
↵* Appendix 1 is available from https://www.cfp.ca. Go to the full text of the article online and click on the CFPlus tab.
Competing interests
None declared
The opinions expressed in commentaries are those of the authors. Publication does not imply endorsement by the College of Family Physicians of Canada.
This article is eligible for Mainpro+ certified Self-Learning credits. To earn credits, go to https://www.cfp.ca and click on the Mainpro+ link.
La traduction en français de cet article se trouve à https://www.cfp.ca dans la table des matières du numéro de mai 2023 à la page e98.
- Copyright © 2023 the College of Family Physicians of Canada
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