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Canadian Consensus Conference On the Appropriate Use Of Fluoride Supplements For the Prevention Of Dental Caries In Children 

Hardy Limeback, PhD, DDS
Amid Ismail, BDS, MPH, DrPH
David Banting, DDS, PhD
Pamela DenBesten, DDS, MS
John Featherstone, M.Sc., PhD
Paul J. Riordan, BDS, MPH, PhD

[ Background | Scientific Presentations | Development Of More Appropriate Fluoride Recommendations | Modification Of the New Recommendations and the Consensus Building Process | Conference Recommendations For Daily Fluoride Supplements | Algorithm For Fluoride Supplement Usage | Acknowledgements | References



Dental fluorosis is an early sign that children have ingested more than optimum amounts of fluoride. Water fluoridation has been in use for more than 50 years. In most developed countries, the prevalence of dental caries has dramatically decreased among the population, from the levels seen in the first six decades of this century. The decline has occurred in both fluoridated and non-fluoridated areas and there is a consensus among experts that the widespread availability of fluoride in water, toothpaste, gels, mouth rinses and other products has had a significant role in causing this decline.

The decline in the prevalence and severity of dental caries has also occurred in Canada, where there is evidence that dental caries are more prevalent in Canadians with low education status (less than 12 years of education) than those with high education status (college or university education). The shift and clustering of dental caries and the increase in the prevalence of dental fluorosis in Canadian children, led some experts to question the rationale for the routine and universal application of fluoride products.

An April 1992 conference, co-chaired by Drs. Chris Clark and Hardy Limeback, involving fluoride experts from Canada and the United States, resulted in the proposal of several new guidelines for the appropriate use of fluoride products. A major recommendation called for the severe restriction of fluoride supplements associated with the development of dental fluorosis.

The 1992 revision of the Canadian recommendation for fluoride supplements was proposed for the following reasons: widespread use of fluoridated toothpastes in Canada and evidence that young children ingest approximately one-third of the paste placed on the toothbrush; increased availability of fluoride in bottled soft drinks and other fluids in Canada; weak scientific evidence supporting the effectiveness of fluoride supplements; the finding that children of highly educated parents have multiple exposures to fluoride products early in life; and the observation that the daily use of fluoride supplements is difficult to follow by population groups who have high prevalence of dental caries. It is believed that fluoride supplements taken in single daily doses, in tablet or lozenge form, increase the risk of dental fluorosis more than fluoridated water because the tissues forming tooth enamel are highly sensitive to fluoride levels in the serum or the bone.

The 1992 Canadian fluoride conference resulted in a more conservative fluoride supplement schedule. This schedule was subsequently approved by the Canadian Dental Association (CDA). The CDA recommended that fluoride tablets not be given to babies and toddlers (birth to 3 years) and that 3 to 5-year-old children living in areas where the fluoride in the drinking water is less then 0.3 parts per million, should receive 0.25 mg of fluoride per day (or 0.5 mg of fluoride per day if fluoridated toothpaste is not used regularly). While most health care professionals accepted this new schedule, others, including some in the dental profession, continued to recommend the American Dental Association (ADA) fluoride schedule to Canadian residents.

This has raised a number of legal and academic questions, the main one being: should fluoride supplements in tablet form continue to be recommended for small children whose front teeth are susceptible to dental fluorosis, and if so, what fluoride schedule is most appropriate? Thus, despite a five-year period of adjustment after the CDA endorsed the recommendations of the 1992 fluoride conference, the confusion about which fluoride supplement schedule was most appropriate for Canadians was still not resolved. Early in 1997, CDA invited Dr. Hardy Limeback to organize a follow-up international conference to examine the current literature and determine if any further modification should be made to existing fluoride recommendations.

Prominent clinical scientists were invited to thoroughly re-examine the evidence for and against the use of fluoride supplements, present their findings in comprehensive reviews (to be published elsewhere), and develop new and more appropriate recommendations, with a particular focus on fluoride supplements. Additionally, the CDA involved representatives from various dental, medical and pharmaceutical organizations in a consensus building process. The ADA was invited but declined to send a representative. The pediatric medical specialists (Canadian Pediatric Society) were represented at this conference but the Canadian Medical Association was unable to send a representative.

The following is a summary of the conference held in Toronto on November 28 and 29, 1997. Brief explanations of the agenda and the recommendations that resulted from the conference are presented in this Journal article. Full conference proceedings will be published in an upcoming issue of Community Dentistry and Oral Epidemiology.

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Scientific Presentations

These participants were charged with developing new guidelines for fluoride use, in Canada, based on their analysis of the current evidence.

1. John Featherstone
A review of how daily low doses of fluoride from fluoride supplements (and fluoridated water) work to prevent and control dental caries.

2. Pamela DenBesten
A review of how the biological mechanism of low daily doses of fluoride causes dental fluorosis.

3. Amid Ismail
A review of the clinical evidence showing fluoride supplements are a primary risk factor for dental fluorosis in non-fluoridated areas.

4. David Banting
A review of the fluoride supplement recommendations in countries outside North America.

5. Hardy Limeback (Conference Chair)
A re-examination of the pre-eruptive and post-eruptive mechanism of the anti-caries effects of fluoride.

6. Paul J. Riordan
A risk-benefit analysis of fluoride supplements for young children, with a focus on preschoolers (children 5-years-old or younger).

Representatives of Organizations (additional voting participants in the consensus building process)

Dr. Jim Tynan, College of Dental Surgeons of Saskatchewan

Dr. Anil Joshi, New Brunswick Dental Society

Dr. Olva Odlum, Manitoba Dental Association

Dr. Gordon Thompson, Alberta Dental Association

Dr. Robert MacGregor, Nova Scotia Dental Association

Dr. Michel Levy, Montreal Public Health Department

Dr. Nina Wang, Norwegian Board of Health

Ms. Frances Hachborn, Canadian Pharmacists Association

Dr. John Godel, Canadian Pediatric Society

Dr. Pierre Gagnon, Order of Dentists of Quebec

Dr. Lawrence Yanover, Canadian Academy of Pediatric Dentistry

Dr. James Leake, Canadian Association of Public Health Dentistry

Dr. Christopher Clark, College of Dental Surgeons of British Columbia

Other, non-voting CDA participants, included Mr. Brian Henderson, Dr. Benoit Soucy (conference co-organizer), Dr. Louis Dubé, Major Euan Swan and Dr. John O’Keefe (Editor, JCDA). Dr. O’Keefe moderated the second day of the conference. Many observers, including some members from the organized anti-fluoride movement, also attended the conference.

All scheduled scientific presenters delivered their papers on the first day of the conference, and the group discussed the current scientific evidence on the risks and benefits of fluoride supplements. On the second day, representatives of participating organizations made brief presentations outlining their own fluoride supplement recommendations and how these recommendations were developed.

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Development Of More Appropriate Fluoride Recommendations

The scientific presenters were then charged with developing appropriate fluoride supplement recommendations based on the latest scientific information. They were, however, asked to be sensitive to the legitimate concerns of the various health care providers, especially those organizations of specialists (e.g. pediatric dentists and pediatricians) focusing on protecting the dentitions of children, ages three or younger.

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Modification Of the New Recommendations and the Consensus Building Process

The scientific presenters and organization representatives were then given the opportunity to discuss the recommendations in an open session (with input from the observers). Modifications were made to the recommendations. After consensus building through further modification of the recommendations, the group at the table was asked to vote on the acceptance of the new recommendations. Consensus was achieved with only one abstention (vote not registered by one participant who left early).

The following is a summary of the consensus recommendations developed at this fluoride conference. These recommendations were widely circulated to the various dental professional organizations, as well as the medical and pharmaceutical professions, for feedback before submission to CDA’s board of governors for approval. At the CDA board meeting in March of this year, the new fluoride supplementation schedule was approved (see J Can Dent Assoc 1998; 64:339-41). It must be noted, however, that at the time of writing, the CDA board of governors has not endorsed all the recommendations of the conference. Health care professionals would be well advised to take into consideration the recommendations and footnotes that accompany the fluoride schedule before implementing its use on individual patients and groups at risk for developing dental decay.

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Conference Recommendations For Daily Fluoride Supplements (Fluoride Drops, Chewable Tablets and Lozenges)

Underlying Considerations:

The numerals in brackets following a statement reflect the level of the evidence used to support the specific affirmation. The hierarchy of levels of evidence (see Table I) is obtained from Canadian Task Force on the Periodic Health Examination: The periodic health examination: 2. 1987 update. Can Med Assoc J 1988; 138:618-26.

1. The primary mechanism of action of fluoride to prevent dental decay is topical. (Evidence level II-3, Recommendation B)..1-3

2. Water fluoridation is an effective delivery method of topical fluoride. (Evidence level II-1, Recommendation B).4-6

3. Fluoridated toothpaste is an effective delivery method of topical fluoride (Evidence level I, Recommendation A).7 The CDA guidelines for appropriate use of fluoridated dentifrices are recommended (a pea size amount of toothpaste or gel used to brush the teeth at least twice a day).

4. Ingestion of more than the recommended daily dose of fluoride is associated with an increased risk of dental fluorosis. (Evidence level II-2, Recommendation E).8,9

5. In the absence of adequate topical fluoride exposure (e.g. fluoridated toothpaste or water) additional fluoride products may be provided in the form of drops, chewable tablets or lozenges. The effectiveness of these products in preventing dental caries is low in school-aged children (Evidence Level II-2, Recommendation C) and is not well evaluated in infants and toddlers. (Evidence level II-3, Recommendation C).10

6. In the case of very high carious challenge, the use of topical fluorides alone may be insufficient to prevent caries (i.e. additional fluoride may produce no net benefit and other measures such as anti-microbial therapy and diet change may be required). (Evidence level III, Recommendation C).11

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 Table I
Quality Of Evidence and Classification Of Recommendations
Level of Evidence Description
I: Evidence obtained from at least one properly randomized controlled trial.
II-1: Evidence obtained from well-designed controlled trials without randomization.
II-2: Evidence obtained from well-designed cohort or case control analytic studies, preferable from more than one centre or research group.
II-3: Evidence obtained from comparisons between times and places with or without the intervention. Dramatic results in uncontrolled experiments (such as the results of treatment with penicillin in the 1940s) could also be included in this category.
III: Opinions of respected authorities, based on clinical experience, descriptive studies or reports of expert committees.
Recommendations for preventive manoeuvres
A There is good evidence to support the recommendation.
B There is fair evidence to support the recommendation.
C There is poor evidence to support the recommendation, but a recommendation could be made on other grounds.
D There is fair evidence to support the recommendation of exclusion.
E There is good evidence to support the recommendation of exclusion.

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Algorithm For Fluoride Supplement Usage

The following decision-making protocol is recommended for use by qualified health care providers in determining the need for fluoride supplements (in this context “child” can mean an individual or a targeted population).

First, ask the following question: Does the child brush his or her teeth (or have teeth brushed by parent or guardian) using fluoridated toothpaste at least twice a day?

If the answer is NO, then supplemental topical fluoride exposure should be provided according to Table II.
If the answer is YES, then answer the following question: In your judgment, is the child susceptible to high dental caries activity?

If your answer is NO, then fluoride supplements are NOT required.
If your answer is YES, then supplemental topical fluoride exposure should be provided according to Table II.

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 Table II
Dosage Of Daily Fluoride Supplement Based On Fluoride In Water Supply
Age of child < 0.3 ppm 0.3 - 0.6 ppm > 0.6 ppm
0 - 6 months none none none
> 6 months - 3 years 0.25 mg/day none none
>3 years - 6 years 0.50 mg/day none none
> 6 years 1.00 mg/day none none

The first visit to the dentist should occur before the age of one year.
Parents must be informed of risk/benefit of fluoride supplements.
Labels on fluoride drops, chewable tablets and lozenges should reflect the above recommended fluoride schedule.
Health care providers should provide written instructions on the appropriate use of fluorides.

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The authors thank Benoit Soucy for co-organizing the conference, Richard McCoy, Anne Bauer and Brian Henderson for staff support and John O’Keefe for moderating the second day of the conference. A web site dedicate to this conference (with additional information) can be found at

Dr. Limeback is associate professor and acting head, Preventive Dentistry, Faculty of Dentistry, University of Toronto.

Dr. Ismail is professor, Department of Cariology, Restorative Sciences and Endodontics, School of Dentistry, University of Michigan.

Dr. Banting is professor of community dentistry, Faculty of Medicine and Dentistry, School of Dentistry, University of Western Ontario.

Dr. DenBesten is associate professor and chair of the Division of Pediatric Dentistry, School of Dentistry, University of California, San Francisco.

Dr. Featherstone is professor and interim chair, Departments of Restorative Dentistry and Dental Public Health and Hygiene, School of Dentistry, University of California, San Francisco.

Dr. Riordan is research dental officer, Dental Services, Health Department of Western Australia.

Reprint requests to: Dr. Hardy Limeback, Head of Preventive Dentistry, Faculty of Dentistry, University of Toronto, 124 Edward St., Toronto, ON M5G 1G6.

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11. Driscoll WS, Nojwack-Raymer R, Selwitz R, Li S-H, Heifetz SB. A comparison of the caries preventive effects of fluoride mouthrinsing, fluoride tablets and both procedures combined: final results after eight years. J Public Health Dent 1992; 52; 111-6.

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