Fluoride

Protecting All Children’s Teeth

Fluoride

Introduction

Fluoride is the negatively charged ionic form of the element fluorine that hasa high affinity for calcium. It plays an important role in the prevention ofdental caries.

Although the primary mechanism of action of fluoride in preventing dentalcaries is topical, systemic mechanisms are also important. Fluoride acts inthe following ways to prevent dental caries:

1. It enhances remineralization of the tooth enamel. This is the most important effect of fluoride in caries prevention. 

2. It inhibits demineralization of the tooth enamel.  

3. It makes cariogenic bacteria less able to produce acid from carbohydrates.

Learner Objectives

Upon completion of this presentation, participants will be able to:

State the 3 mechanisms of action of fluoride in dental caries prevention.

Summarize the available sources of fluoride and their relative benefits.

List strategies to minimize the development of fluorosis. Discuss the fluoride supplementation guidelines. Recognize the various forms of fluorosis and recall their

prevalence.

Fluoride Facts

Fluoride has been available in the United States since the mid-1940’s.  In 2008, 64.3% of the population served by public water systems received optimally fluoridated water. Public water fluoridation practice varies by city and state. Water fluoridation was recognized by the Centers for Disease Control and Prevention (CDC) as one of the 10 greatest public health achievements of the 20th century.  

Fluoride Facts, continued

There is strong evidence* that community water fluoridation is effective in preventing dental caries. 

The recommended concentration of fluoride in drinking water was decreased in 2011 from 0.7-1.2 mg/L to 0.7 mg/L.

Clinicians should balance the benefits of fluoride against the risk of fluorosis when deciding whether to fluoridate water.

Water filters may decrease the fluoride content of community water. Activated charcoal filters and cellulose filters have a negligible effect; reverse osmosis filters and water distillation remove almost all fluoride from water.

Systemic Sources of Fluoride

Fluoride can be ingested through:

Drinking water Other beverages Foods Toothpaste Fluoride supplements

Bottled Water

No one source exists to tell consumers the fluoride content in bottled waters.

The US Food and Drug Administration (FDA) does not require that fluoride content be listed on the labels of bottled waters.

It is appropriate to assume that children whose only source of water is bottled are not receiving adequate amounts of fluoride from that source.

Commercial Beverages and Foods

Many foods and beverages are made with community fluoridated water, so they contain fluoride.

Foods such as seafood and certain teas can also have a naturally highfluoride content.

This must all be taken into account when determining daily fluoride intake.

Infant Nutrition

Human breast milk contains almostno fluoride, even when the nursingmother drinks fluoridated water.

Powdered infant formula containslittle or no fluoride, unless mixedwith fluoridated water. The amountof fluoride ingested will depend onthe volume of fluoridated watermixed with the formula.

Toothpaste

Toothpaste’s effects are mainly topical, but some toothpaste is swallowed by children and is available systemically.

Strategies to Minimize Toothpaste Ingestion   Discourage children from swallowing toothpaste.  Encourage spitting of toothpaste.  Supervise brushing until spitting can be ensured.   Limit the amount of toothpaste on the toothbrush.

Fluoride Supplements

Supplements should be considered especially for patients at high risk for dental caries whose community water source is suboptimal.

Supplements are available in liquid, tablet, or lozenge form.

Fluoride Supplements, continued

CDC Quality of Evidence to Support the Use of Fluoride Supplements

Children 6 years and younger: Grade II-3. Strength of recommendation of C with targeted effort at populations at high risk for dental caries.   Children 6-16 years: Grade 1. Strength of recommendation of A with targeted effort at populations at high risk for dental caries. Pregnant women: Quality of evidence against providing fluoride supplementation to pregnant women to benefit their children is Grade 1. Strength of recommendation of E (good evidence to reject the use of the modality).

Fluoride Supplements, continued

The 2010 ADA guideline* recommends fluoride supplements be prescribed only to children at high risk for caries development. Strength of recommendation: B

The United States Preventive Services Task Force recommends fluoride supplementation be prescribed at recommended doses to children older than 6 months whose primary water source is deficient in fluoride. Strength of recommendation: B

Topical Sources of Fluoride

Following are the most common forms of topical fluoride:

Toothpaste Fluoride mouthrinses Fluoride gels Fluoride varnish

Toothpaste

Toothpaste is the most recognizable source of topical fluoride.

The addition of fluoride to toothpaste began in the 1950s.

Brushing with fluoridated toothpaste is associated with a 24% reduction in decayed, missing, and filled tooth surfaces.

The CDC concluded that the quality of evidence for fluoridated toothpaste in reduction of caries is grade 1. Strength of recommendation is A for usein all persons.

Fluoride Mouthrinses

Mouthrinses containing fluoride are recommended in a “swish and spit”manner.

Mouthrinses are available over the counter. Frequency of use ranges from daily to weekly.

The CDC concluded that quality of evidence for fluoride mouthrinses is Grade 1. Strength of recommendation is A with targeted effort atpopulations at high risk for dental caries.

Fluoride Gels

Fluoride gels are professionally applied or prescribed for home use under professional supervision. They are typically recommended for use twice per year.

The CDC concluded that the quality of evidence for using fluoride gel to prevent and control dental caries in children is Grade 1. Strength of recommendation is A, with targeted effort at populations at high risk for caries.

Fluoride Varnish

Varnishes are a professionally applied, sticky resin of highly concentrated fluoride (up to 22,600 ppm).

In the United States, fluoride varnishhas been approved by the FDA for useas a cavity liner and root desensitizer,but not specifically as an anti-cariesagent.

For caries prevention, fluoride varnish is an “off label” product.

Fluoride Varnish

Application frequency for fluoride varnish ranges from 2 to 6 times per year.

The use of fluoride varnish leads to a 33% reduction in decayed, missing, and filled tooth surfaces in the primary teeth and a 46% reduction in the permanent teeth.

The CDC concluded that the quality of evidence for using fluoride varnishto prevent and control dental caries in children is Grade 1. Strength ofrecommendation is A, with targeted effort at populations at high risk fordental caries.

Community Water Fluoridation

The goal of community water

fluoridation is to maximize dental

caries prevention while minimizing the

frequency of enamel fluorosis.

In January 2011, the US Department

of Health and Human Services announced

that the optimal fluoride concentration

is 0.7 ppm.

Because there is geographic variability in community water fluoridation, it is important to know fluoride content of the water children consume.

Water Fluoridation

The US Environmental Protection Agencyrequires that all community water supply systems provide customers an annual report on the quality of water, including fluoride concentration. Providers can contact the local water authority for this information.

Fluoride content of a town’s water can also be determined byaccessing CDC’s My Water's Fluoride Web site.

Well Water

Wide variations in the natural fluoride concentration of well water sources exist.

Private wells should be tested for fluoride concentration before prescribing supplements. Testing can be done through local and state public health departments or through private laboratories.

Fluoride Supplementation

When access to community water fluoridation is limited, fluoride can besupplemented in liquid, tablet, or lozenge form.

Fluoride supplements require a prescription. A 2010 ADA guideline*recommends fluoride supplements be prescribed only to children determinedto be at high risk for the development of caries.

Supplementation Dosing Schedule

The American Academy of Pediatrics, American Dental Association (ADA), and American Academy of Pediatric Dentistry (AAPD) have developed the following dosing schedule for fluoride supplementation:

1. All sources of fluoride must be considered, including primary drinking water, other sources of water, prescriptions from the dentist, fluoride mouthrinse in school, and fluoride varnish.  2. Supplementation should be provided if fluoride access is limited. 3. Children younger than 6 months and older than 16 years should not be supplemented. 4. Children who have adequate access to (and are drinking) appropriately fluoridated community water should not be supplemented.

Fluorosis

Fluorosis is caused by an increased intake of fluoride.

Mild forms of fluorosis appear as chalk-like, lacy markings on the tooth’s enamel.

In the moderate form of dental fluorosis, a white opacity can be seen on more than 50% of the tooth.

Severe fluorosis results in brown, pitted, brittle enamel.

Fluorosis

Dental fluorosis occurs during tooth development.

Permanent teeth are more susceptible to fluorosis than primary teeth.

The most critical ages of susceptibility are 0 to 6 years, especially between the ages of 15 and 30 months.

After 7 or 8 years of age, dental fluorosis cannotoccur because the permanent teeth are fullydeveloped, although not erupted.

Prevalence of Fluorosis

The prevalence of dental fluorosis has increased in the United States from 22.8% in 1986-1987 to 32% in 1999-2002.

This can be attributed to the increased availability and ingestion of multiple sources of fluoride by young children, including:

Foods Beverages Toothpaste Other oral care products Dietary fluoride supplements

Prevalence of Fluorosis, continued

Some form of dental fluorosis is found in the following age groups*:   40% of US children ages 6-11 years  49% of 12- to 15-year-olds  42% of 16- to 19-year-olds

Most of this fluorosis is mild and barely noticeable by non-dental healthprofessionals.

Prevalence of Fluorosis, continued

Although the effects of dental fluorosis are mainly aesthetic, the increased prevalence mandates that health professionals be aware of all possible sources of fluoride before considering supplementation.

Fluorosis and Toothpaste

Ingestion of toothpaste increases therisk of enamel fluorosis.

If fluoridated toothpaste is used,strategies to limit the amountswallowed include limiting the amountplaced on the brush and observing thechild as they brush.

Fluorosis and Toothpaste

According to the AAPD, the best way to minimize a child's risk for fluorosis is to limit the amount of toothpaste on the toothbrush.

The AAPD suggests a “smear” of toothpaste for children younger than 2 years of age and a "pea-sized" amount for children ages 2 to 5.

Fluorosis and Toothpaste

For children younger than 2, the CDC suggests the pediatrician consider fluoride levels in the community drinking water, other sources of fluoride, and factors likely to affect susceptibility to dental caries when weighing the risk and benefits of fluoride toothpaste. The CDC does not give specific advice on how much toothpaste to use in children younger than 2.

For children younger than 6, the CDC recommends that parents:

1. Limit toothbrushing to 2 times a day. 2. Apply less than a pea-sized amount to the toothbrush. 3. Supervise tooth brushing and encourage children to spit out excess toothpaste.4. Keep toothpaste out of the reach of young children to avoid accidental ingestion.

Fluorosis and Toothpaste

A 2007 Maternal and Child Health Bureau expert panel recommended: All children at high risk for dental caries use fluoride toothpaste Children younger than age 2 use a “smear” of toothpaste Children aged 2-6 years use a slightly larger, “pea-sized” amount

The AAP endorses this recommendation.

When deciding whether to use fluoridated toothpaste in children younger than 2, the panel recommends considering: The child's risk of dental caries The risk of dental fluorosis The benefit of the topical application in the form of fluoridated toothpaste

Question #1

What is the most critical age of susceptibility to fluorosis of the

permanent teeth?

A. Between 0 and 15 months of age.B. Between 15 and 30 months of age. C. Between 30 and 45 months of age. D. The risk of fluorosis in the permanent teeth is equal across all

ages.E. None of the above.

Answer

What is the most critical age of susceptibility to fluorosis of the

permanent teeth?

A. Between 0 and 15 months of age.B. Between 15 and 30 months of age. C. Between 30 and 45 months of age. D. The risk of fluorosis in the permanent teeth is equal across all

ages.E. None of the above.

Question #2

True or False? The most important mechanism of action of fluoride

is a systemic effect.

A. True. B. False.

Answer

True or False? The most important mechanism of action of fluoride

is a systemic effect.

A. True. B. False.

Question #3

Which of the following is the most important function of fluoride in

caries prevention?

A. Fluoride enhances remineralization of tooth enamel. B. Fluoride inhibits demineralization of tooth enamel.C. Fluoride negatively affects the acid producing capabilities of

cariogenicbacteria.D. Fluoride displaces sugars from the surface of the teeth.E. All of the above are equally important.

Answer

Which of the following is the most important function of fluoride in

caries prevention?

A. Fluoride enhances remineralization of tooth enamel. B. Fluoride inhibits demineralization of tooth enamel.C. Fluoride negatively affects the acid producing capabilities of

cariogenicbacteria.D. Fluoride displaces sugars from the surface of the teeth.E. All of the above are equally important.

Question #4

True or False? Fluoride supplements should be prescribed for high-riskchildren whose community water source is suboptimal.

A. TrueB. False

Answer

True or False? Fluoride supplements should be prescribed for high-risk children whose community water source is suboptimal.

A. TrueB. False

Question #5

Which of the following is a symptom of mild fluorosis?

A. A white opacity on more than 50% of the tooth.B. Dark spots on the teeth.C. Brown, pitted, brittle enamel.D. Chalk-like, lacy markings on the enamel.E. None of the above.

Answer

Which of the following is a symptom of mild fluorosis?

A. A white opacity on more than 50% of the tooth.B. Dark spots on the teeth.C. Brown, pitted, brittle enamel.D. Chalk-like, lacy markings on the enamel.E. None of the above.

References

1. American Academy of Pediatric Dentistry. Guideline on Infant Oral Health Care. Council on Clinical Affairs. Reference Manual 2011. 33(6): 124-128. 2. American Academy of Pediatric Dentistry. Policy on Early Childhood Caries (ECC): Classifications, Consequences, and Preventive Strategies. Pediatr Dent 2011, 33(6): 47-49.3. American Dental Association Council on Scientific Affairs. Professionally applied topical fluoride. Evidence-based clinical recommendations. JADA. August 1, 2006. 137(8): 1151-1159. 4. Berg J, Gerweck C, Hujoel PP, et al. Evidence-Based Clinical Recommendations Regarding Fluoride Intake from Reconstituted Infant Formula and Enamel Fluorosis. A Report of the American Dental Association Council on Scientific Affairs. JAMA. January 2011 vol. 142(1): 79-87. 5. Centers for Disease Control and Prevention. Recommendations for using fluoride to prevent and control dental caries in the United States. MMWR. 2001; 50(RR-14): 1-42. Available online at: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5014a1.htm. Accessed November 20, 2006.

References, continued

6. Centers for Disease Control and Prevention. Surveillance for Dental caries, Dental sealants, Tooth Retention, Edentulism, and Enamel Fluorosis-United States, 1988-1994 and 1999-2002. MMWR Surveillance Summaries. 2005. 54(03);1-44. Available online at: http://www.cdc.gov/mmwr/preview/mmwrhtml/ss5403a1.htm. Accessed November 20, 2006. 7. Centers for Disease Control and Prevention. Using Fluoride to Prevent and Control Tooth Decay in the United States Fact Sheet, updated Jan 2011. www.cdc.gov/fluoridation/fact_sheets/fl_caries.htm8. Department of Health and Human Services. HHS Recommendation for Fluoride Concentration in Drinking Water for Prevention of Dental Caries. Federal Register. Vol. 76(9): January 13, 2011. 9. Krol DM. Dental caries, oral health, and pediatricians. Curr Probl Pediatr Adolesc Health Care. 2003; 33(8):253-270.10. Lewis CW, Milgrom P. Fluoride. Pediatr Rev. 2003; 24(10):327-336.11. Lewis DW, Ismail AI. Periodic health examination: 1995 update: 2. Prevention of dental caries. The Canadian Task Force on the Periodic Health Examination. Can Med Assoc J. 1995; 152(6): 836-46.

References, continued

12. Marinho VCC, Higgins JPT, Logan S, Sheiham A. Fluoride varnishes for preventing dental caries in children and adolescents. The Cochrane Database of Systematic Reviews 2002, Issue 1. Art. No.: CD002279. DOI: 10.1002/14651858.CD002279. This version first published online: 21 January 2002 in Issue 1, 2002. 13. Marinho VCC, Higgins JPT, Logan S, Sheiham A. Topical fluoride (toothpastes, mouthrinses, gels, or varnishes) for preventing dental caries in children and adolescents. The Cochrane Database of Systematic Reviews 2003, Issue 1. Art. No.: CD002782. DOI: 10.1002/14651858.CD002782. This version first published online: 20 January 2003 in Issue 1, 2003. 14. Oral health in America: A Report of the Surgeon General. Rockville MD: US Department of Health and Human Services, National Institute of Dental and Craniofacial Research, National Institutes of Health; 2000. Available online at: http://www.nidcr.nih.gov/DataStatistics/SurgeonGeneral. Accessed November 20, 2006. 15. Rozier RG, Adair S, Graham F, et al. Evidence-Based Clinical Recommendations on the Prescription of Dietary Fluoride Supplements for Caries Prevention. A Report of the American Dental Association Council on Scientific Affairs. JADA. December 2010 vol. 141(12): 1480-1489.

References, continued

16. US Environmental Protection Agency. 40 CFR Part 141.62. Maximum contaminant levels for inorganic contaminants. Code of Federal Regulations 2002:428-9. 17. US Environmental Protection Agency. 40 CFR Part 143.3 National secondary drinking water regulations. Code of Federal Regulations 2002; 614. 18. United States Preventive Services Task Force. Guide to clinical preventive services, 2010-2011. Available online at: http://www.ahrq.gov/clinic/pocketgd.htm. Accessed January 28, 2011.