1. Water Fluoridation November 21, 2007 Abdullah S. Al-Swuailem BDS, MS, MPH, Dr PH

2. Water Fluoridation Water Fluoridation: Water Fluoridation: - “It is the adjustment of the natural flouride concentration of fluoride-deficient water supplies to the recommended level for optimal dental health” - Water fluoridation was first initiated on January 25, 1945 in Grand Rapids, Michigan

3. Water Fluoridation Historical background: Historical background: - Clinical discovery phase: Dr. Fredrick McKay (Colorado Spring Dentist) noted in 1920s that some of his patients exhibited a varied degree of tooth hypo-mineralization and staining (mottled teeth). Dr. McKay attributed this to something in the drinking water. - by 1930, a chemist named Churchill identified fluoride in the drinking water (14 ppm)

4. Water Fluoridation Historical background: Historical background: - Epidemiology phase (1933-1945): “Dean’s 21-City study” correlation of different levels of fluoride to dental caries and dental fluorosis. Optimal level of fluoride 0.7 – 1.2 ppm. Fig 8-1

6. Water Fluoridation Historical background: Historical background: - Demonstration phase (1945-1954): Series of clinical studies assessing the effect of adding fluoride to drinking water. e.g Dean’s study in Grand Rapids-Michigan with Muskegon- Michigan as control. Approximately 60% reduction in caries incidence (DMFs)

7. Water Fluoridation Historical background: Historical background: - Technology transfer phase (1950) - The Year 2010 Health Objectives for the Nation: 75% of the population on community-water systems should live in communities with fluoridated water by the year 2010. - In 1992, 62% of the population served by centralized pipe-water system have fluoridated water. - World-wide implementation of water fluoridation

8. Water Fluoridation Mechanism of action: Mechanism of action: 1. Systemic fluoride incorporated into tooth structure by replacing hydroxyl group in hydroxyapatite to form a more resistant fluoroapatite 2. Fluoride present in saliva may inhibit the enzymatic activity of cariogenic bacteria and thereby inhibit acids production 3. Remineralize tooth enamel that has been demineralized by bacterial acids

9. Water Fluoridation Issues with water fluoridation: Issues with water fluoridation: - Dental fluorosis - Cost of water fluoridation: average cost of water fluoridation per person per year is $0.50 (average cost for simple tooth filling = $62) average cost of water fluoridation per person per year is $0.50 (average cost for simple tooth filling = $62) For every $1 spent on fluoridation, $80 is saved in treatment cost.

10. Water Fluoridation Issues with water fluoridation: Issues with water fluoridation: - Optimal fluoride levels: Table 8-5

11. Water Fluoridation Issues with water fluoridation: Issues with water fluoridation: - Partial exposure to fluoride? - Effect on different tooth surfaces - Safety of water fluoridation

13. Water Fluoridation Issues with water fluoridation: Issues with water fluoridation: - Chemicals used: sodium fluoride, sodium silicofluoride, and hydrofluosilcic

14. Water Fluoridation Other fluoride vehicles: Other fluoride vehicles: - Salt fluoridation: NaF or CaF2 - Milk fluoridation: 5 mg of F added to 1 liter of milk - Fluoride mouthrinses - Supplemental fluoride tablets