Fluorides for the Future:Science, Policy and the Public’s Health

John W. Stamm, DDS

Univ. of North Carolina

2008 Statewide Oral Health Conference

Greensboro, NC

July 15, 2008

Presentation Aims1. Economic context for dental prevention

and care

2. Update on water fluoridation

3. Touch on fluoride toothpastes

4. Mention Fluoride supplements

5. Consider dental fluorosis as a driver for change in public health practice

6. Imagine some future policy and research options

U.S. Dental Expenditures

$91.5 billion in 2006 (est.) $305.0 per capita 4.3% of total health expenditures 44.4% out of pocket 49.5% via insurance 5 % from Medicaid 1% other sources

US Centers for Medicare and Medicaid Services and US Department of Commerce, Jan-Feb, 2008.

Water fluoridation: It is the foundation for caries prevention!

“The four horsemen of public health are the pasteurization of milk, the purification of water, the immunization against disease, and controlled fluoridation. None of these gains has been achieved easily -- none of the four measures has endured more severe obstruction than fluoridation.”

Dr. Luther Terry

Surgeon General, USPHS

Water Fluoridation

Benefits of FluoridesLess dental decayLess restorative dentistryLess tooth lossLess painLess absenteeism from school, workFewer iatrogenic disordersGenerally more esthetic dentitionCost-effective prevention

Water Fluoridation USA

184 million persons in the U.S. live in fluoridated communities (2006)

69.2% of population with water systems receive F water (2006)

44/50 largest U.S. cities are fluoridated Cost per person per year $0.72 (2003):

$0.68 (water system > 50K)$0.98 (water system 10K – 50K)$3.00 (water system <10K)

Populations Receiving Optimally Fluoridated Water – US, 1992 - 2006

MMWR 07-11-2008 National trend:

1992 -- 62.1%

2000 -- 65.0%

2006 -- 69.2 % Goal for 2010 remains at 75%

CDC MMWR Weekly, July 11, 2008/57(27):737-741.

North Carolina – Population Receiving Optimally Fluoridated Water in 2006

North Carolina 2006 5,689,906 people, representing 87.6% of those on community water systems.

Rank 20th in the nation Represents 4.3% improvement over 2000

CDC MMWR Weekly, July 11, 2008/57(27):737-741.

Water Fluoridation Effectiveness Historical estimates revealed 40 - 50 percent

effectiveness in caries reduction, based on permanent dentition in children

NIDR 1986-87 children’s survey found DMFS 18% lower in children with life-long fluoridated water intake, versus those with life-long non-fluoridated water intake.

The 18% difference underestimates water fluoridation’s impact on caries prevention because of epidemiological factors and food/beverage manufacturing and distribution practices.

Water Fluoridation Effectiveness 18 - 20 % effectiveness, year after year, is still a

significant public health benefit With 44/50 of the largest US cities fluoridated,

manufactured foods/beverages carry dietary fluoride to non-fluoride communities, exerting benefit there

Mean annual cost of $0.68 – $3.00 per person makes fluoridation the most cost-effective caries preventive available.

Powerful passive caries prevention measure Disproportionally benefits those at highest risk to

caries; fulfills social equity objectives.

Current Recommendations for Water Fluoridation

Continue water fluoridation at currently recommended levels (0.7 – 1.2 ppm F)

Control F concentration within 0.2 ppm F of recommended levels for the region

Ensure that funding exists for fluoridation equipment maintenance and appropriate replacement

Allocate budget to ensure professional development for filtration plant personnel

Fluoridate 75% of U.S. population by 2010

Dentifrices are a Major

Fluoride Vehicle!

The Toothpaste Market is Big, and it Delivers Fluoride

World Toothpaste Market, US$ mn

Region 2000 2006 % Growth

Asia Pacific 3,328 4,208 20.9

Australasia 136 209 53.7

Eastern Europe 628 1,197 90.6

Latin America 1,837 2,125 15.7

Mid. East & Africa 557 729 30.9

North America 2,103 2,267 07.8

Western Europe 2,546 3,702 45.4

World 11,135 14,437 29.7Adapted from Euromonitor Intl.

Fluoride Dentifrices Fluoride dentifrice use is nearly

ubiquitous in the United States Fluoride dentifrices (1000-1100 ppm F)

are a major caries prevention modality Efficacy of 15%-30% may be expected NaF dentifrices modestly (6-7%)

superior to MFP dentifrices Marginal cost of including fluoride in a

dentifrice is very low, resulting in good cost-effectiveness

Optimizing Fluoride Dentifrices for Children

• There is a dose-response curve for dentifrice fluoride concentration and caries increment reduction

• Dose response relationship is less clear for concentrations under 1000 ppm F

• Clinical trials of low dose (~500 ppm F) fluoride dentifrices have demonstrated efficacy, though not consistently

Effect of Dentifrice Fluoride Level on32-month Caries Increment, 12-year Olds

DMFSDentifrice Sample Increment

Significance

250 ppmF 365 4.29

1000 ppmF 360 3.61 p<.05

Adapted from Mitropoulos et al, 1984

Current Recommendations for Fluoride Dentifrices

• Recommend use of 1000-1100 ppm F dentifrices for adults

• Recommend children (2-6 years) use only pea-sized quantity of F dentifrice on the brush

• Reserve higher F concentration dentifrices for use in high caries risk patients, age > 12 years

Multi-function Toothpaste: The Current Trend in Dentifrice Development

Six Functions of Modern Toothpastes 1. Caries prevention

Fluoride delivery Biofilm control Demineralization (diminish) Remineralization (promote)

2. Plaque control and gingivitis prevention

3. Calculus prevention

4. Tooth whitening (extrinsic stain reduction)

5. Dentin hypersensitivity reduction

6. Breath freshening

Touching briefly on fluoride supplements!

Fluoride Supplements

• In the past, approximately 50% of children had some experience with fluoride supplements

• Consistent compliance below 20%

• Cost approximately $3-$20 per year

• Effectiveness is very variable

• Significant risk factor for enamel fluorosis

• Current supplement schedule adopted 1994

U.S. Fluoride Supplement Schedule,1994

Community Fluoridation LevelAge <0.3ppm 0.3-0.6ppm >0.6ppm

0 mos.- 6 mos. 0 0 06 mos.- 3 yrs.0.25mg 0 03 yrs. - 6 yrs. 0.50mg 0.25mg 06 yrs. - 16 yrs. 1.0 mg 0.50mg 0

ADA, AAP, AAPD

Current Prescribing Guidelines for Fluoride Supplements

1. Establish F level in child’s drinking water 2. Establish appropriate use of F dentifrice3. Prescribe F supplements, liquids or tablets,

according to 1994 schedule4. Do not prescribe F supplements in areas

served by fluoridated water (F>0.6 ppm)5. Do not prescribe pre-natal F supplements6. Recommend F supplements only to high

caries risk patients

Prevention with fluorides has benefited US school children

0

2

4

6

8

10

Mea

n D

MF

T

5 6 7 8 9 10 11 12 13 14 15 16 17

Age

NH 99-02 NH 88-94 NIDR 86-87 NIDR 79-80 NH 71-73

Trends in Dental Caries Prevalence in the Permanent Dentition (DMFT). United States

1970s to 1990s

56

78

95-9

2.2

3.3 3.5 3.7

2.8 3.1

2.2 2.4 2.6 2.82.7

2.61.7 1.8 2.0 2.01.9

1.9

1.8

1.71.7

2.1

1.7 1.81.7 2.0

1.8

2.3

1.7 1.9

Age

NH 99-02 NH III 88-94 NIDR 86-7 NIDR 79-80 NH 71-74

Trends in Dental Caries in the Primary Dentition Trends in Dental Caries in the Primary Dentition

(dft), United States, 1970s to 2000(dft), United States, 1970s to 2000

Mean dft

A Clean and Healthy Mouth

But fluorosis persists, and intake studies raise concerns!

MODERATE

Severe

Risks Associated with Excess Fluoride Ingestion

Two categories of risk

1. Acute toxicity

2. Chronic toxicity -- dental & skeletal

Risk Sources for Enamel Fluorosis

Risk from fluoride containing water consumption

Risk from fluoride supplement use/misuse

Risk from ingestion of dentifrices Risk from other forms of chronic,

excess fluoride ingestion

Dental Fluorosis

• As much as 70% of the risk of dental fluorosis may be related to inappropriate early use of fluoride dentifrices and a history of fluoride supplement ingestion

• Other simultaneous forms of fluoride ingestion will account for the balance of fluorosis risk

Prevalence of Enamel Fluorosis among US 5-17yr. Old School

Children, 1986-87

None 77.0%

Questionable

Very mild 21.6%

Mild

Moderate 1.1%

Severe 0.3%

QUESTIONABLE

VERY MILD

Association of Enamel Fluorosis with F Supplement Use Started Before Age 1 Yr.

Period of F Adjusted 99% Conf.

Suppl. Use odds ratio Limit

None 1.0 ---

Year 1 1.8 0.8 - 4.4

Year 3-6 2.2 0.8 - 5.8

Years 1 & 3-6 4.0 1.4 - 11.4

Pendrys & Katz, 1988

Association of Enamel Fluorosis with F Supplements, 8-Yr Olds, Umea

Age

Supplement Fluorosis Relative Confidence

Use Started N Yes No Risk Limits (95%)

Never 20 3 17 1.0 ---

36 mos. 6 2 4 1.2 0.2 - 33.8

24 mos. 8 3 5 2.5 0.3 - 32.9

12 mos. 51 30 21 3.9 1.9 - 47.1

6 mos. 21 17 4 5.4 3.8 - 176.0

Adapted from Holm & Anderson, 1982

Association of Enamel Fluorosis with Early Use of F Dentifrice, Controlling on Mother’s Education, 8-10 Yr. Olds, Toronto, Can.

Age Brushing Number Odds Confidence

Started (mos.) Cases Controls Ratio Limits (95%)

Late (25-60) 12 54 1.0 --

Early (6-24) 53 20 11.0 4.8 – 25.2

Adapted from Osuji et al, 1988

Fluoridation Policy Changes: International Perspectives

Australia, Canada, Hong Kong, Ireland and Singapore have adopted the following public health policies:Reduce water fluoride to 0.6 – 0.7 ppm F.Cease recommending fluoride supplements. Introduce pediatric fluoride toothpastes, i.e. 450 –

600 ppm F.Monitor dietary intake of fluoride (0 – 36 months).

Fluoride Policy for the Future:A 3-Element Change Agenda

1. Restrict fluoride supplement prescriptions to very high caries risk children

2. Advocate strongly and persistently for pediatric fluoride toothpastes

3. Investigate and potentially revise the recommended water fluoride concentration

An Agenda for Fluoride Research 1. Surveillance research should be increased to

study water fluoridation compliance

2. Epidemiological studies are needed to document trends in fluorosis prevalence

3. More research is needed on fluoride ingestion in the first 36 months of life

4. Need to re-evaluate the relationship of ambient air temperature, fluid intake, caries prevention and fluorosis prevalence.

5. More research on gene-fluoride interactions

Thank you for your courtesy and attention!!