Government regulation on fluoride and fluoridation

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Government regulation on fluoride and fluoridation Powered By Docstoc
					Government regulation on
fluoride and fluoridation
             Howard Pollick BDS, MPH
          Health Sciences Clinical Professor
  Dept. of Preventive & Restorative Dental Sciences
             School of Dentistry, UCSF



       Dental Public Health Seminar, Fall 2011
                Government Agencies

           • Federal
             • HHS
             • EPA
             • Joint HHS/EPA announcement January 7, 2011

           • Healthy People 2020 (Public-Private Partnership)

           • State
             • California – Cal EPA - OEHHA



10/25/11                             2                  Government Regulation on Fluoride
           American Public Health Association


           • APHA 2011 Annual Session, WASHINGTON DC

           • Oral Health Section

           • 3368: Healthy fluoridated communities.
                 Grand Hyatt, Independence Ballroom C

           • Monday Oct 31, 2:30 – 4 pm

           • http://apha.confex.com/apha/139am/webprogram
             /Session33325.html

10/25/11                           3                Government Regulation on Fluoride
           National Oral Health Conference
                    April 11, 2011
• Community Water Fluoridation: implications of new data for policy
  and practice
• EPA Dose-Response and Exposure Assessments for Fluoride
• Joyce Donahue
• Evidence Supporting the 2011 "Proposed HHS Recommendation for
  Fluoride Concentration in Drinking Water for Prevention of Dental
  Caries"
• Eugenio Beltran
• http://www.nationaloralhealthconference.com/index.php?page=prese
  ntations2011

10/25/11                          4                    Government Regulation on Fluoride
              Federal Register notice
           January 13, 2011 (76 FR 2383)
            Proposed HHS Recommendation for Fluoride
             Concentration in Drinking Water for Prevention of
             Dental Caries


           • This updated guidance is intended to apply to community
             water systems that are currently fluoridating or will
             initiate fluoridation.


           • This guidance is based on several considerations that
             include:

10/25/11                                 5                    Government Regulation on Fluoride
              Federal Register notice
           January 13, 2011 (76 FR 2383)
      Proposed HHS Recommendation for Fluoride Concentration in
       Drinking Water for Prevention of Dental Caries
      Scientific evidence related to effectiveness of water fluoridation
       on caries prevention and control across all age groups.

      Fluoride in drinking water as one of several available fluoride
       sources.

      Trends in the prevalence and severity of enamel fluorosis.

      Current evidence on fluid intake in children across various
       ambient air temperatures.

10/25/11                               6                     Government Regulation on Fluoride
              Federal Register notice
           January 13, 2011 (76 FR 2383)
•     HHS recommends an optimal fluoride concentration of 0.7 mg/L for community water
      systems based on the following information:

•     Community water fluoridation is the most cost-effective method of delivering fluoride
      for the prevention of tooth decay;

•     In addition to drinking water, other sources of fluoride exposure have contributed to
      the prevention of dental caries and an increase in enamel fluorosis prevalence;

•     Significant caries preventive benefits can be achieved and risk of fluorosis reduced at
      0.7 mg/L, the lowest concentration in the range of the USPHS recommendation.

•     Recent data do not show a convincing relationship between fluid intake and ambient
      air temperature. Thus, there is no need for different recommendations for water
      fluoride concentrations in different temperature zones.

10/25/11                                        7                           Government Regulation on Fluoride
           Response by the ADA
• ADA supports HHS’ science-based recommendation to set the
  level for optimally fluoridated water at 0.7 parts per million.


• The adjustment should provide an effective level of fluoride to
  reduce the incidence of tooth decay while minimizing the rate of
  fluorosis in the general population.


• Reaffirms the federal government’s longstanding commitment to
  community water fluoridation and justifies the ongoing need for
  communities to establish, upgrade and maintain an effective
  public water fluoridation infrastructure.
10/25/11                          8                   Government Regulation on Fluoride
           Access to fluoridated water
• December 31, 2008, CDC estimate
• 16,977 community water systems provided fluoridated water to
  196 million people.

• 95% of that population receiving fluoridated water was served by
  community water systems that added fluoride to water, or purchased
  water with added fluoride from other systems.

• The remaining 5% were served by systems with naturally occurring
  fluoride at or above the recommended level.

• 64% of the total U.S. population

• 72.4% of the U.S. population served by public water systems
10/25/11                             9                   Government Regulation on Fluoride
               Healthy People 2020
     • Increase the proportion of the U.S. population served by
       community water systems with optimally fluoridated water to
       79.6%

     • An increase of 10% over the 2008 level of 72.4%

     • http://www.healthypeople.gov/2020/topicsobjectives2020/obj
       ectiveslist.aspx?topicId=32




10/25/11                           10                    Government Regulation on Fluoride
     US EPA - Friday January 7, 2011
           • EPA announced plans to review the current national primary
             drinking water standard for fluoride - the maximum amount
             of fluoride allowed in drinking water.
           • Establishes a maximum contaminant level (MCL) and
             maximum contaminant level goal (MCLG) for naturally
             occurring fluoride in drinking water
           • Current MCL/MCLG - 4.0 mg/L to protect against crippling
             skeletal fluorosis.
           • “EPA’s new analysis will help us make sure that people
             benefit from tooth decay prevention while at the same time
             avoiding the unwanted health effects from too much
             fluoride.”

10/25/11                                11                   Government Regulation on Fluoride
                              US EPA
     • EPA is acting on a 2006 report from the National Research
       Council (NRC)

     • NRC committee recommended that severe enamel fluorosis is
       not just a cosmetic effect of excessive fluoride intake during
       tooth development as previous reports had indicated

     • Severe enamel fluorosis is an adverse health effect due to
       increasing the risk for dental caries as a result of pitting of
       enamel in severe enamel fluorosis.

     • Caries is considered an adverse health effect, by implication.

10/25/11                              12                    Government Regulation on Fluoride
                             US EPA

           • Following the recommendation from the NRC, the U.S.
             EPA conducted a dose-response assessment for
             severe enamel fluorosis

           • Updated the exposure assessment for fluoride from
             that supporting the 1986 MCLG/MCL of 4.0 mg/L.

           • EPA released the dose response and exposure
             assessments in January 2011 when EPA announced its
             plans to review the drinking water standard.


10/25/11                             13                 Government Regulation on Fluoride
           http://water.epa.gov/lawsregs/rulesregs/regulatingcontaminants/sixyearr
           eview/upload/2011_Fluoride_QuestionsAnswers.pdf
10/25/11                                   14                       Government Regulation on Fluoride
           Federal Register: March 29, 2010 (Volume 75, Number 59)

• Fluoride - a. Background.
•     EPA published the current NPDWR for fluoride on April 2, 1986 (51 FR 11396 (USEPA,
      1986c)). (National Primary Drinking Water Regulations (NPDWRs or primary standards) are
      legally enforceable standards that apply to public water systems.)

•     The NPDWR established an MCLG and an MCL of 4.0 mg/L.

•     The MCLG was developed from a lowest effect level for crippling skeletal fluorosis of 20
      mg/day with continuous exposures over a 20-year or longer period.

•     The lowest-observed-adverse-effect level (LOAEL) was divided by an uncertainty factor of 2.5
      and a drinking water intake of 2 liters/day (L/day) to obtain the MCLG.

•     Drinking water was considered to be the only source of exposure for the calculation. At the
      same time, EPA published a secondary maximum contaminant level (SMCL) for fluoride of
      2.0 mg/L to protect against enamel fluorosis, which was considered to be an adverse
      cosmetic effect.

•     PWSs (Public Water Systems) exceeding the fluoride SMCL must provide public notification
      to their customers.

10/25/11                                          15                           Government Regulation on Fluoride
           Federal Register: March 29, 2010 (Volume 75, Number 59)

• Fluoride - a. Background.
• Fluoride is unique because of its beneficial effects at low level exposures, and

• because it is voluntarily added to some drinking water systems as a public
  health measure for reducing the incidence of cavities among the treated
  population.

• The amount of fluoride added to drinking water for fluoridation ranges from
  0.7 to 1.2 mg/L, depending on ambient air temperatures.

• The decision to fluoridate a water supply is made by the State or local
  municipality, and is not mandated by EPA or any other Federal entity.



10/25/11                                 16                       Government Regulation on Fluoride
           Federal Register: March 29, 2010 (Volume 75, Number 59)

• Fluoride - b. Technical Reviews.

•     As a result of the first Six-Year Review of the fluoride NPDWR (67 FR 19030 (USEPA, 2002c)
      (preliminary); 68 FR 42908 (USEPA, 2003e) (final)),

•     EPA requested that the National Research Council (NRC) of the National Academies of Science
      (NAS) conduct a review of the recent health and exposure data on orally ingested fluoride.

•     In 2006, the NRC published the results of their evaluation in a report entitled, Fluoride in Drinking
      Water: A Scientific Review of EPA's Standards.

•     Based on its review, NRC concluded that severe enamel fluorosis is an adverse health effect when
      it causes confluent thinning and pitting of the enamel, a situation that compromises the function
      of the enamel in protecting the dentin and eventually the pulp from decay and infection.

•     There was consensus among the committee that severe enamel fluorosis is an effect that should
      be avoided and that ``exposure at the MCLG clearly puts children at risk of developing severe
      enamel fluorosis.''

10/25/11                                              17                              Government Regulation on Fluoride
           Federal Register: March 29, 2010 (Volume 75, Number 59)

• Fluoride - b. Technical Reviews ...

• In addition, the committee examined the scientific data on the impact of
  fluoride on the strength and structure of bone and the majority concluded
  that the MCLG ``is not likely to be protective against bone fractures.''

• NRC recommended that EPA use the available dose-response data for the
  effects of fluoride on

• severe enamel fluorosis and skeletal fractures

• in combination with data on the relative contribution of drinking water to total
  fluoride exposure

• to identify an MCLG that would be protective against these effects.


10/25/11                                18                       Government Regulation on Fluoride
       COMMITTEE ON FLUORIDE IN DRINKING WATER


•     JOHN DOULL (Chair), University of       •    HARDY LIMEBACK, University of
      Kansas Medical Center, Kansas City           Toronto, Ontario, Canada

•     KIM BOEKELHEIDE, Brown University,      •    CHARLES POOLE, University of North
      Providence, RI                               Carolina at Chapel Hill, Chapel Hill

•     BARBARA G. FARISHIAN, Washington, •          J. EDWARD PUZAS, University of
      DC                                           Rochester, Rochester,

•     ROBERT L. ISAACSON, Binghamton          •    NYNU-MAY RUBY REED, California
      University, Binghamton, NY                   Environmental Protection Agency,
                                                   Sacramento
•     JUDITH B. KLOTZ, University of
      Medicine and Dentistry of New Jersey,   •    KATHLEEN M. THIESSEN, SENES Oak
      Piscataway                                   Ridge, Inc., Oak Ridge, TN

•     JAYANTH V. KUMAR, New York State        •    THOMAS F. WEBSTER, Boston University
      Department of Health, Albany                 School of Public Health, Boston, MA
10/25/11                                      19                        Government Regulation on Fluoride
 EPA Office of Water (OW) Reports

     • Fluoride: Dose-Response Analysis For Non-cancer Effects

     • Fluoride: Exposure and Relative Source Contribution Analysis

     • Federal Register notices of January 19, 2011 (76 FR 3422)
       and April 6, 2011 (76 FR 19001)



     • http://water.epa.gov/action/advisories/drinking/fluoride
       _index.cfm

10/25/11                            20                   Government Regulation on Fluoride
           Threshold for Severe Enamel Fluorosis


• 2006 National Research Council’s report,

• Fluoride in Drinking Water: A Scientific Review of EPA’s Standards

• Prevalence of severe enamel fluorosis

• Graph – Figure 4-1

• 94 prevalence estimates from studies in the United States

• No empirical evidence of severe enamel fluorosis where water
  supply has <2 ppm
10/25/11                          21                  Government Regulation on Fluoride
             EMPIRICAL EVIDENCE: No severe enamel fluorosis
           where there is less than 2.0 ppm fluoride in drinking water




10/25/11                               22                      Government Regulation on Fluoride
                            Benchmark Modeling of the Dean Data
                                               Dichotomous-Hill Model with 0.95 Confidence Level
                                                  Dichotomous-Hill
                                                BMD Lower Bound
                      0.7


                      0.6


                      0.5
                                                      BMDL= 1.87 mg F/L
Fraction Affected




                      0.4                                  BMD= 2.14 mg F/L

                      0.3


                      0.2


                      0.1


                        0
                                               BMDL        BMD
                                  0        1           2             3     4          5         6   7   8
                                                                         Concentration (mg/L)


               The BMDL is the statistical estimate for the drinking water concentration in the 1930’s where the fluoride in
               the water led to severe enamel fluorosis in 0.5 % of the population at the lower bound 95% confidence level.

                                                      U.S. EPA Office 23 Water
                                                                      of
     EPA’s Benchmark Dose (BMD) Methodology

• Benchmark Dose (BMD): An exposure due to a dose of a
  substance associated with a specified low incidence of risk, generally
  in the range of 1% to 10%, of a health effect; or the dose associated
  with a specified measure or change of a biological effect.

• BMDL: A lower one-sided confidence limit on the BMD.

• 1.87 mg/L fluoride in drinking water – Estimated THRESHOLD
  for severe enamel fluorosis to protect 99.5% of children

• http://www.epa.gov/ncea/bmds/bmds_training/methodology/intr
  o.htm#BMD


10/25/11                           24                    Government Regulation on Fluoride
           The latest US data on enamel fluorosis

• NIDR 1986-87 data vs NHANES 1999 - 2004 data
• Prevalence and Severity of Dental Fluorosis in the United States,
  1999-2004
• 1986-1987 - 22.6% of adolescents aged 12-15 had dental fluorosis
• 1999-2004 - 40.7% of adolescents aged 12-15 had dental fluorosis.
• The estimates for severe alone were statistically unreliable.


• http://www.cdc.gov/nchs/data/databriefs/db53.htm

10/25/11                            25                    Government Regulation on Fluoride
26
           Caveats limiting the interpretation of an apparent increase
               in prevalence of enamel fluorosis (Dean’s Index):


• 1986-87 NIDR school-based                 • Oversampled ethnic minorities

• 1999-2004 NHANES - household              • Unknown Residence Histories?

• # of Examiners (14 vs 2-4)                • Fluoride sources?
                                              Water fluoride concentration?
• Questionable vs very mild                   Swallowing toothpaste?
  NIDR – combined 47.4%;
  NHANES – combined 48.2%                   • Inappropriate fluoride
                                              supplements?
• Combined moderate and severe
  (NIDR – 1.3%; NHANES - 3.6%)              • 1992-94 changes in recommended
                                              personal fluoride exposure –
• less than 1% had severe enamel              cannot be evaluated until after
  fluorosis                                   2004

10/25/11                               27                       Government Regulation on Fluoride
                  EPA OW Estimates
• Mean Fluoride Concentration in U.S. drinking water = 0.87 mg/L *

• a. using the 90th percentile drinking water intake for consumers only.

• b. using mean drinking water intake

• Other fluoride exposure estimates are average values

• RfD based on a severe enamel fluorosis prevalence of ≤ 0.5% of the
  population exposed during the period of vulnerability

      * 1.87 mg/L for BMDL should not be confused with this value of 0.87 mg/L.
      The tap water fluoride concentration of 0.87 mg/L was the national average
      from the EPA monitoring results for 2002-2005 from systems that detected
      fluoride. Systems with no detected fluoride were not included.

10/25/11                                  28                      Government Regulation on Fluoride
       Exposure Estimates Relative to the RfD:
       a. 90th Percentile Drinking Water Intake
              3.5


                    Above the black line –
                3
                    risk for severe enamel fluorosis
              2.5




                2

           mg/day

              1.5




                1




              0.5




                0
                    0.5 to <1   1 to <4        4 to <7          7 to <11      11 to 14   >14
                                                         Age Range in Years


Mean fluoride concentration = 0.87 mg/L using the 90th percentile drinking water intake for consumers
only. Other exposure estimates are average values; RfD based on a severe fluorosis prevalence of ≤ 0.5%
of the population exposed during the period of vulnerability

                                                       29
                                          U.S. EPA Office of Water
     Exposure Estimates Relative to the RfD:
       b. Average Drinking Water Intake
     3
          Above the black line –
          risk for severe enamel fluorosis
    2.5




     2




    1.5

mg/day


     1




    0.5




     0
          0.5 to <1   1 to <4       4 to <7          7 to <11      11 to 14   >14
                                              Age Range in Years


     Mean fluoride concentration = 0.87 mg/L; mean drinking water intake

                                              30
                                U.S. EPA Office of Water
           EPA Office of Water (OW)
     • Reference Dose (RfD) for fluoride of 0.08 mg/kg/day based on
       severe enamel fluorosis as an adverse health effect.

     • mean water intake and estimated contribution from foods (in
       1942) to determine the RfD of 0.08 mg/kg/day

     • OW used a model based on 1942 paper (Dean) to produce a
       value of 1.87 mg/L in drinking water as the lower bound of a
       confidence interval that would protect 99.5% of children from
       developing severe enamel fluorosis


10/25/11                           31                  Government Regulation on Fluoride
• Fluoride: Exposure and Relative Source Contribution Analysis

• calculates the relative contribution of fluoride from drinking
  water to the total intake of fluoride for various age groups under
  today’s conditions

• takes into account fluoride intake from food, beverages,
  toothpaste, and sulfuryl fluoride

• Using the 90th percentile of water intake to derive this relative
  source contribution (RSC), per EPA policy

• This in effect lowers the concentration of F in drinking water that
  would trigger exceeding the RfD and leading to >0.5% of children
  developing severe enamel fluorosis.


10/25/11                          32                   Government Regulation on Fluoride
• When all sources of fluoride exposure/intake are considered,
  including swallowing fluoride toothpaste (ages 1-4 years) and
  infant formula (<12 months of age) reconstituted with
  fluoridated water

• Using the EPA OW RSC, at 0.87 mg/L fluoride in drinking water
  and intake at the 90th or even 50th percentile water intake,
  >0.5% of children would be at risk for severe enamel fluorosis

• So we’ve gone from 1.87 ppm to 0.87 ppm leading to >0.5%
  children developing severe enamel fluorosis.

• More analysis is needed on the methodology for estimating the
  intake of fluoride from the other sources to determine the
  adequacy of the EPA’s estimates.

10/25/11                         33                  Government Regulation on Fluoride
• Does this set the bar too low?


• Or should all water systems strive to be at 0.7 ppm as the
  optimum concentration to minimize both dental caries and
  severe dental fluorosis.


• Practical considerations – feasibility – would place limitations on
  those water systems that have naturally occurring fluoride
  greater than 0.7 ppm


• The operating range (control limits) for fluoridated systems will
  possibly be set at 0.6 – 0.8 ppm or 0.6 – 1.0 ppm
10/25/11                           34                  Government Regulation on Fluoride
      • If you look at the possible formulas for calculating
        MCLG, in a worst case, it could go as low as 0.6 mg/L.

      • EPA likely won’t go that low, and there is no way they
        would set the MCL so low for reasons of practicality
        and cost to communities to defluoridate due to higher
        naturally occurring fluoride in drinking water.

      • But they might go as low as 1.2 mg/L for the MCL.

      • What would this do for the future of water fluoridation
        programs?


10/25/11                           35                 Government Regulation on Fluoride
             Effect of change by HHS to
              0.7 ppm on EPA estimate
           • One action that would potentially impact the EPA
             RSC assessment and the sulfuryl fluoride action is
             the proposed change to the optimum fluoride
             concentration by HHS to a standard 0.7 mg/L
             nationwide. This would lower the national average
             fluoride concentration in drinking water and would
             likely lower the direct and indirect drinking water
             intake of fluoride.



10/25/11                             36                  Government Regulation on Fluoride
 Consequences of a lower MCL?

      • The SMCL would no longer be needed and would be dropped.

      • EPA could set the MCLG very close to the optimum for CWF and set the
        MCL fairly low as well, depending on their technical and cost analyses
        for systems to defluoridate.

      • Water systems with natural F above whatever the MCL is set at would be
        mandated to defluoridate.

      • EPA would be urged to appropriate grant funds to water systems to
        reduce their F level if exceeding MCL and fund additional research on
        the health effects including enamel fluorosis.


10/25/11                                  37                      Government Regulation on Fluoride
                        Sulfuryl Fluoride

           • EPA is proposing to remove sulfuryl fluoride, a pesticide, from the
             U.S. market because of the residual fluoride that children would
             consume.

           • EPA estimates that the fluoride intake from sulfuryl fluoride of
             0.03 to 0.06 mg/day for children up to 7 years, depending on the
             age group, increases the risk for severe enamel fluorosis.

           • Objections were first filed by the Fluoride Action Network (FAN)
             and Beyond Pesticides/National Coalition Against the Misuse of
             Pesticides. FAN and Beyond Pesticides also requested a hearing
             on their objections. At a later date, FAN and Beyond Pesticides
             were joined by the Environmental Working Group (hereinafter the
             three parties are referred to as ``the Objectors’’)

10/25/11                                     38                      Government Regulation on Fluoride
           EPA http://www.epa.gov/pesticides/sulfuryl-
                     fluoride/questions.html


• How much of total fluoride exposure is due to sulfuryl fluoride?

• Residues of fluoride due to fumigating commodities, mills, and
  bakeries with sulfuryl fluoride constitute less than three percent
  of the total exposure to fluoride.

• Since sulfuryl fluoride is an important alternative to methyl
  bromide, and because sulfuryl fluoride use is a very small
  contributor to overall exposure, EPA has proposed a three year
  phase out of use of sulfuryl fluoride.


10/25/11                         39                   Government Regulation on Fluoride
           Bottled Water and Fluoride

           • The EPA and the FDA
           • 1979 Memorandum of Agreement specifying that the EPA
             regulates safe drinking water in accordance with the Safe
             Drinking Water Act, and
           • the FDA regulates bottled water as a consumer beverage
             under the Food, Drug, and Cosmetic Act (Federal Register,
             Volume 44, No. 141, July 20, 1979).


           • http://www.cdc.gov/fluoridation/fact_sheets/bottled_wate
             r.htm

10/25/11                                 40                   Government Regulation on Fluoride
                     FDA and Fluoride
•     The Food and Drug Administration (FDA) does not have regulatory responsibility
      for public water supplies; that is the responsibility of the Environmental Protection
      Agency. To my knowledge FDA has made no statements regarding approving
      substances added to water - I don't know why we would since it is not our area of
      responsibility. With regard to your question about whether the Agency has made
      statements about the safety and efficacy of fluoridation, I would say only that we
      have approved fluoride containing products, dentifrices and mouthrinses, for the
      prevention of caries.

      John V. (Jake) Kelsey, DDS, MBA
      Dental Team Leader
      Division of Dermatologic and Dental Drug Products (HFD-540)
      FDA

•     March 10, 2003 – email to Howard Pollick


10/25/11                                      41                         Government Regulation on Fluoride
                EPA, FDA, and Fluoride
 • The Safe Drinking Water Act (SDWA), passed in 1974 and amended in 1986
   and 1996, gives the Environmental Protection Agency (EPA) the authority to
   set drinking water standards.

           (Reference: http://water.epa.gov/lawsregs/rulesregs/sdwa/ )

 • The regulation of water is divided between the Environmental Protection
   Agency and FDA. EPA has the responsibility for developing national standards
   for drinking water from municipal water supplies. FDA regulates the labeling
   and safety of bottled water.

           (Reference: http://www.fda.gov/Food/FoodSafety/Product-
           SpecificInformation/BottledWaterCarbonatedSoftDrinks/ucm077079.htm )


10/25/11                                      42                         Government Regulation on Fluoride
           Latest Research




10/25/11          43         Government Regulation on Fluoride
• Fluoride was introduced into dentistry over 70 years ago, and it is
  now recognized as the main factor responsible for the dramatic
  decline in caries prevalence that has been observed worldwide.

• However, excessive fluoride intake during the period of tooth
  development can cause enamel fluorosis.

• In order that the maximum benefits of fluoride for caries control
  can be achieved with the minimum risk of side effects, it is
  necessary to have a profound understanding of the mechanisms
  by which fluoride promotes caries control.
• Buzalaf MA, Pessan JP, Honório HM, ten Cate JM. Mechanisms
  of action of fluoride for caries control. Monogr Oral Sci. 2011;22:97-114




10/25/11                               44                       Government Regulation on Fluoride
• In the 1980s, it was established that fluoride controls caries
  mainly through its topical effect.

• Fluoride present in low, sustained concentrations (sub-ppm
  range) in the oral fluids during an acidic challenge is able to
  absorb to the surface of the apatite crystals, inhibiting
  demineralization.

• When the pH is re-established, traces of fluoride in solution will
  make it highly supersaturated with respect to
  fluorhydroxyapatite, which will speed up the process of
  remineralization.
• Buzalaf MA, Pessan JP, Honório HM, ten Cate JM. Mechanisms
  of action of fluoride for caries control. Monogr Oral Sci. 2011;22:97-114


10/25/11                               45                       Government Regulation on Fluoride
• The mineral formed will then preferentially include fluoride and
  exclude carbonate, rendering the enamel more resistant to
  future acidic challenges.
• Topical fluoride can also provide antimicrobial action.
• Fluoride concentrations as found in dental plaque have biological
  activity on critical virulence factors of S. mutans in vitro, such as
  acid production and glucan synthesis, but the in vivo implications
  of this are still not clear.
• Evidence also supports fluoride’s systemic mechanism of caries
  inhibition in pit and fissure surfaces of permanent first molars
  when it is incorporated into these teeth pre-eruptively.
• Buzalaf MA, Pessan JP, Honório HM, ten Cate JM. Mechanisms
  of action of fluoride for caries control. Monogr Oral Sci. 2011;22:97-114


10/25/11                              46                     Government Regulation on Fluoride
• the main mechanisms of action of fluoride rely on its topical use since
  low, sustained levels of fluoride in the oral fluids can significantly
  control caries progression and reversal.
• However, this concept does not invalidate the use of ‘systemic’
  methods such as fluoridated water. More than 60 years of intensive
  research attest to the safety and effectiveness of this measure to
  control caries.
• In this case, however, it should be emphasized that despite being
  classified as a ‘systemic’ method of fluoride delivery (as it involves
  ingestion of fluoride), the mechanism of action of fluoridated water to
  control caries is mainly through its topical contact with the teeth while
  in the oral cavity or when redistributed to the oral environment by
  means of saliva.
• Buzalaf MA, Pessan JP, Honório HM, ten Cate JM. Mechanisms
  of action of fluoride for caries control. Monogr Oral Sci. 2011;22:97-114


10/25/11                               47                       Government Regulation on Fluoride
• Since fluoridated water is consumed many times a day, the high
  frequency of contact of fluoride present in the water with the
  tooth structure or intraoral fluoride reservoirs helps to explain
  why water fluoridation is so effective in controlling caries,
  despite having fluoride concentrations much lower than fluoride
  toothpastes, for example.

• This general concept can be applied to all methods of fluoride
  use traditionally classified as ‘systemic’. In the light of the current
  knowledge regarding the mechanisms by which fluoride control
  caries, this system of classification is in fact misleading.
• Buzalaf MA, Pessan JP, Honório HM, ten Cate JM. Mechanisms
  of action of fluoride for caries control. Monogr Oral Sci. 2011;22:97-114



10/25/11                               48                       Government Regulation on Fluoride
                MESSAGING

           I thought fluoride was good
           for me, so why should I be
           concerned about getting too
           much of it?


10/25/11                49        Government Regulation on Fluoride
           2 headed coin




10/25/11         50        Government Regulation on Fluoride
                Old Model –
           2 headed fluoride coin




10/25/11             51         Government Regulation on Fluoride
               New Model –
           2 headed fluoride coin




10/25/11             52         Government Regulation on Fluoride
 Not all enamel fluorosis is the same

           • Severe Enamel Fluorosis is rare




10/25/11                             53        Government Regulation on Fluoride
  Moderate and Severe Fluorosis and ‘Moderate/Severe’ Caries




          “Moderate/Severe Caries”        “Moderate/Severe Caries”

 Photographs from Forum on Water Fluoridation in Ireland, 2002
5/21/11                              54                              Fluoride & Tooth Decay Prevention
            Goal – Minimal caries;
              minimal fluorosis
• Optimum
• Safety
• Public Health measures
  • For everyone
  • Targeted approach

• Individual measures
• Caries risk assessment
• Fluorosis risk assessment
• Clinical judgment

                              Caries   Caries – Abscess
                                 55
            Infant Formula, Other
               Fluoride Sources




     Associations Between Fluorosis of Permanent Incisors and Fluoride Intake From
     Infant Formula, Other Dietary Sources and Dentifrice During Early Childhood.
     Steven M. Levy, Barbara Broffitt, Teresa A. Marshall, Julie M. Eichenberger-Gilmore,
     and John J. Warren J Am Dent Assoc 2010; 141(10): 1190-120
56
               CDA leads efforts to keep
                fluoride off Prop 65 list
           • Representatives of the California Dental Association,
             CDA Foundation, and California Statewide Fluoridation
             Advisory Council attended a hearing of the California
             Office of Environment Health Hazard Assessment
             (OEHHA), Carcinogen Identification Committee (CIC)
             on Oct. 12, 2011 which reviewed fluoride and its salts.
           • CDA and its partners applaud the committee’s
             determination that fluoride should not be listed under
             Proposition 65 as a chemical known to cause cancer. The
             committee carefully reviewed all of the scientific research
             available on fluoride and its salts and determined that the
             evidence fails to show that fluoride is linked to cancer.


10/25/11                                 57                   Government Regulation on Fluoride
              Fluoride is not a carcinogen

      •    http://oehha.ca.gov/prop65/public_meetings/cic092311.html

      •    Transcript not yet available

      •    Great team effort with a lot of collaboration and planning between the
           CHPA and CDA and CDPH beforehand.

      •    Catherine Hayes's testimony was very useful, as well as testimony from
           Richard Adamson and Jay Murray;

      •    We have to thank the Consumer Healthcare Products Association and
           Barbara Kochanowski for directing CHPA's effort.

      •    Don Lyman's testimony was also extremely useful in addressing questions
           posed by committee members on trends in osteosarcoma rates with SEER
           data showing no increase even with increasing fluoride exposure.

10/25/11                                      58                       Government Regulation on Fluoride
             Fluoride is not a carcinogen

           • I am so glad we have scientific experts on the
             OEHHA CIC reviewing the science, rather than it
             being a political decision by non-experts such
             as we find on city councils.
           • The evidence just isn't there to list fluoride as a
             carcinogen. So, no additional labels on
             toothpaste and none on water bills indicating
             the listing of fluoride on Prop 65.
           • The FDA would have fought over the labels on
             toothpaste and rinses and such.


10/25/11                             59                 Government Regulation on Fluoride
                    KGO TV Report

           • Panel votes against adding fluoride to
             carcinogen list

           • http://abclocal.go.com/kgo/video?id=83898
             13&syndicate=syndicate&section=

           • Apologies for the advertisement before the
             video




10/25/11                         60               Government Regulation on Fluoride

				
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