Fluoride

• Fluoride


  A mineral that our bodies need in small amounts to stay healthy, found in some foods, drinking water, and oral hygiene products
• Fluoride is the ionic form of the element fluorine
• Fluoride


  • Inhibits or reverses the initiation and progression of dental caries (tooth decay)
  • Stimulates new bone formation
• Fluoride absorption and storage

  1. Most fluoride is absorbed in the gut and stored in bones and teeth

  2. Unabsorbed fluoride is excreted in urine

  3. Children absorb fluoride more efficiently than adults as their teeth and bones are rapidly forming
• Soil, water, plants, and foods contain trace amounts of fluoride
• Most of the fluoride that people consume comes from fluoridated water, foods and beverages prepared with fluoridated water, and toothpaste and other dental products containing fluoride
• Fluoride absorption and retention

  • Approximately 80% or more of orally ingested fluoride is absorbed in the gastrointestinal tract
  • In adults, about 50% of absorbed fluoride is retained, and bones and teeth store about 99% of fluoride in the body
  • The other 50% is excreted in urine
  • In young children, up to 80% of absorbed fluoride is retained because more is taken up by bones and teeth than in adults
• Fluoride's functional role


  • Helps strengthen tooth enamel during growth and development
  • Protects teeth from dental caries by acting in the saliva and creating a layer over teeth to lower damage from acids
  • Helps improve the density and hardness of bones, making them more stable
• Fluoride and tooth decay


  Fluoride combats tooth decay by blocking acid formation by bacteria, preventing demineralization of teeth, and enhancing remineralization of destroyed enamel
• About 99% of the fluoride in the body is in the hard tissues
• Fluoride and dental health

  Fluoride increases tooth mineralization, helps reduce dental enamel demineralization and promote dental enamel remineralization, and helps reduce dentin hypersensitivity
• The relationship between fluoride and dental caries was first noted in the early part of the 20th century
• Fluoride at lower "optimal" concentrations of 0.7 to 1.2 ppm in the water supply imparts protection against development of dental caries and reduces the overall risk of developing fluorosis
• The use of fluorides for the prevention of dental caries is recognized as the most effective dental public health measure in existence
• Fluoride is beneficial to all age groups throughout the life cycle
• Recent statistics show that adults are just as likely to experience new dental caries as children
• Fluoride and bone health

  • Fluoride can stimulate bone cell (osteoblast) proliferation and increase new mineral deposition in cancellous bone
  • The amount of fluoride in the water supply considered optimal to promote oral health (1 ppm or 1 mg/L) is not considered sufficient to stimulate osteoblast activity or prevent osteoporotic fractures
• Evidence from randomized clinical trials is insufficient to support a cause-and-effect relationship between the amount of fluoride in drinking water and bone health status
• Dietary reference values for fluoride

  • Recommended Dietary Allowance (RDA)
  • Adequate Intake (AI)
  • Estimated Average Requirement (EAR)
  • Tolerable Upper Intake Level (UL)
• Adequate intake of fluoride by age and sex

  • Birth to 6 months: 0.01 mg/day
  • 7-12 months: 0.5 mg/day
  • 1-3 years: 0.7 mg/day
  • 4-8 years: 1 mg/day
  • 9-13 years: 2 mg/day
  • 14-18 years: 3 mg/day
  • 19+ years: 4 mg/day
  • Pregnancy: 4 mg/day
  • Lactation: 4 mg/day
• Greater than 70 percent of a person's fluoride comes from drinking fluoridated water
• Other dietary sources of fluoride

  • Brewed black tea and coffee
  • Canned shellfish like shrimp and blue crab
  • Oatmeal
  • Raisins
  • Potatoes
• Fluoride in tea and milk

  • Brewed black tea typically contains higher levels of fluoride than most foods
  • Fluoride concentrations in breast milk and cow's milk are very low
• Types of fluoride application

  • Topical fluorides
  • Systemic fluorides
• Topical fluorides


  • Neutral sodium fluoride
  • Stannous fluoride
  • Acidulated phosphate fluoride (APF)
  • Fluoride varnish
  • Dentifrices
  • Mouth washes
  • Fluoride gels
• Systemic fluorides


  • Community water fluoridation
  • School water fluoridation
  • Salt fluoridation
  • Milk fluoridation
  • Fluoride tablets/drops/lozenges
• Topical fluorides


  Applied to the tooth surface in regular intervals to prevent dental caries
• Indications for topical fluorides

  • Caries-active individuals
  • Children shortly after tooth eruption
  • Individuals with reduced salivary flow or head/neck radiation
  • After periodontal surgery
  • Patients with fixed/removable prostheses or changes in eating/oral hygiene habits
  • Mentally/physically challenged individuals
• Professionally applied topical fluorides

  • Sodium fluoride
  • Stannous fluoride
  • Acidulated phosphate fluoride
  • Fluoride varnish
• Sodium fluoride


  The first fluoride compound used for topical application, provides caries reduction of about 30% with a minimum of 4 applications
• Stannous fluoride


  Used at 8% and 10% concentrations, causes tissue irritation and tooth staining
• Acidulated phosphate fluoride (APF)


  Stable, requires only 2 applications per year, can deposit fluoride deeper in enamel, but has a sour and bitter taste
• Fluoride vehicles


  • Aqueous solutions and gels
  • Thixotropic solutions
  • Fluoridated prophylactic pastes
  • Fluoride varnishes
• Self-applied topical fluorides are low concentration products dispensed by individuals based on dental professional recommendation
• Viscosity


  High under storage conditions, becomes fluid under conditions of high stress
• Fluoridated prophylactic pastes


  If used, the lost fluoride is replenished and there is a significant gain in the concentration of fluoride
• Fluoride varnish


  Increasing the time of contact between enamel surface and topical fluoride agents favours the deposition of fluorapatite and fluorhydroxyapatite
• Duraphat


  A viscous yellow material, containing 22,600 ppm fluoride as sodium fluoride in a neutral colophonium base
• Fluorprotector


  A clear polyurethane based product containing 7000 ppm fluoride from difluorosilane, dispensed in 1ml ampules each containing 6.21 mg of fluoride
• Carex


  Has lower fluoride concentration than Duraphat but has equal efficacy as a caries preventive agent