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Preventing Dental Caries: Community Water Fluoridation - Archived


What the CPSTF Found

Summary of Results

Twenty-one studies qualified for review.

  • Decay rates measured before and after water fluoridation: median decrease of 29.1%among children ages 4 to 17 years when compared with control groups (21 study arms).
  • Decay rates measured after water fluoridation only: median decrease of 50.7% among children ages 4 to 17 years when compared with control groups (20 study arms).
  • Fluoridation was found to help decrease tooth decay both in communities with varying decay rates and among children of varying socioeconomic status.

Nine studies qualified for review of the economic efficiency of community water fluoridation programs.

  • Median cost per person per year for 75 water systems receiving fluoridated water: $2.70 among 19 systems serving < =5000 people to $0.40 among 35 systems serving >=20,000 people (7 studies).
  • Community water fluoridation was cost saving (5 studies).
  • In smaller communities (5000 to 20,000 residents), fluoridation was estimated to be cost-saving where decay incidence in the community exceeds 0.06 tooth surfaces per person annually.

These results were based on a systematic review of all available studies, conducted on behalf of the Task Force by a team of specialists in systematic review methods, and in research, practice and policy related to oral health.

Evidence Gaps

Each Community Preventive Services Task Force (Task Force) review identifies critical evidence gaps—areas where information is lacking. Evidence gaps can exist whether or not a recommendation is made. In cases when the Task Force finds insufficient evidence to determine whether an intervention strategy works, evidence gaps encourage researchers and program evaluators to conduct more effectiveness studies. When the Task Force recommends an intervention, evidence gaps highlight missing information that would help users determine if the intervention could meet their particular needs. For example, evidence may be needed to determine where the intervention will work, with which populations, how much it will cost to implement, whether it will provide adequate return on investment, or how users should structure or deliver the intervention to ensure effectiveness. Finally, evidence may be missing for outcomes different from those on which the Task Force recommendation is based.

Identified Evidence Gaps

  • Community water fluoridation (CWF)
    Most of the evidence indicates that CWF is safe and effective in reducing dental caries in communities. However, important research questions with practical applications remain unanswered, including:
    • What is the effectiveness of laws, policies, and incentives to encourage communities to start or continue water fluoridation?
    • What is the effectiveness of CWF in reducing socioeconomic or racial and ethnic disparities in caries burden?
    • What is the effectiveness of CWF among adults (aged >18 years)?
    • What, if any, are the effects of the increasing use of bottled water and in-home water filtration systems (which may not be fluoridated or may remove fluoride, respectively) on the benefits gained through CWF?
    • How effective is CWF in preventing root-surface caries?
  • School-based or school-linked pit and fissure sealant delivery programs
    The evidence is clear and convincing that sealants delivered through schools and school-affiliated clinics are safe and effective in preventing dental caries among children. Important research questions yet to be answered include:
    • What is the effect of sealant delivery programs among adults aged >18 years (e.g., military recruits)?
    • How do state dental practice laws and regulations affect use of sealants in school-based programs?
    • How do school district oral health policies and curricula affect use of sealants?
    • What is the effectiveness of sealants in primary teeth?
  • Statewide or community-wide sealant promotion programs
    The available evidence of the effectiveness of statewide or community-wide sealant promotion programs was insufficient to support a recommendation by the Task Force. Therefore, research in the following areas is a high priority:
    • What is the effect of public education on awareness, community mobilization (through coalitions), and resource allocation for sealant promotion?
    • What is the effect of professional education, combined with provider reminders and other system-oriented strategies, on knowledge, skills, and appropriate use of sealants?
    • What is the effect of insurance coverage and managed care plans on access to and use of sealants?
    • How cost effective are models of sealant delivery other than school based?

Ecologic Approaches Using Multiple Interventions with Many Targets of Change
Research on ecologic approaches in various settings might involve multiple interventions with many targets of change and desirable health. Estimates of effectiveness might focus on increase in knowledge, behavioral intentions, and behaviors in the short term and the desirable health outcomes mentioned above in the long term. Questions such as the following need to be answered:

  • What is the effect on several oral health outcomes of community-wide interventions that combine environmental change, legislative action, policy change, and social support within families to encourage behavior change?
  • What is the effect on several oral health outcomes of community development coalitions, partnerships, mass media advocacy, and social marketing?
  • What is the effect on several oral health outcomes of multicomponent interventions in selected settings?