Water Fluoridation Flashcards
Define water fluoridation
Controlled addition of fluoride to a public water supply as a public health measure to reduce the incidence of caries
How does water fluoridation work?
Fluoride incorporated into hydroxyapatite crystal - fluorohydroxyapatite more resistant to attack
Saliva promotes remineralisation of early carious lesions
Fluoride interferes with metabolic pathways of bacteria, reducing acid
Mechanisms of water fluoridation?
Pre-eruptive
Post-eruptive
Both
Systemic
Topical
Both
Aims of water fluoridation?
Change distribution of disease in whole population so EVERYONE has the benefits of fluoride
What did Dean et al 1941 find?
More fluoride in water = less caries in 12-14yr olds
More fluoride = more fluorosis
At 1ppm of fluoride in water = most benefit and very little amount of fluorosis = optimum level of fluoride in water
UK ministry health mission - what did they decide after investigating water fluoridation?
Consider adoption of water fluoridation
Demonstration projects in England, Scotland and Wales - found that the DMFT decreased with water fluoridation and increased when the fluoride was removed
Dental caries in the UK features?
Caries in 5 yr olds has decreased e.g. in 70s = dramatic drop as fluoridated toothpaste popular
Lower than in 70s
Low levels of restoration in primary teeth
Continuing reduction in permanent dentition of caries and fillings
Social inequalities remain
What else can be done other than fluoridated water?
Toothpaste >1000ppm
MW NaF 0.05%
Varnish NaF 2.2%
High fluoride concentration toothpaste - 2800ppm and 5000ppm
What to consider before putting fluoride in the water?
Availability of fluoridated toothpaste
Other models of fluoride delivery
Water supply structure - urban, rural environments
Migration patterns = most effective at pre-eruptive tooth stage
Objectives of the York Review?
- Effects of water fluoridation on incidence of caries?
- Benefits over and above those offered by alternative interventions?
- Reduced inequalities?
- Negative effects?
- Difference between natural and artificial fluoridation?
Conclusions of the York Review?
- 6 people need to receive fluoridated water for one extra person to be caries free
- Post 1974 studies - effect over and above other sources of fluoride
- Equity?
- Fluorosis - of aesthetic concern, one additional person for every 22 people receiving fluoridated water
- Artificial vs natural?
Moderate to poor quality evidence
Gaps in knowledge identified
What was the aim of the cochrane review in 2015?
To evaluate effects of fluoride in water on the prevention of tooth decay and dental fluorosis
What did the cochrane review 2015 include?
20 studies on tooth decay (70% before 1975)
135 studies on fluorosis (74% in naturally fluoridated areas)
19 February 2015
What did the cochrane review 2015 find?
Water fluoridation effective in reducing decay levels amongst CHILDREN:
35% in primary teeth
26% in permanent teeth
Increased in no decay:
- 15% primary teeth
- 14% permanent teeth
But studies old
No benefits found in adults
Reducing inequalities - insufficient evidence
Effects of stopping water fluoridation - insufficient evidence
12% fluorosis of aesthetic concern (0.7ppm)
Results comparable with york review
Concerns about quality of included studies
Cost effectiveness of water fluoridation?
Consider nature of water supply
Fluoridation cost effective if population of 200,000
5 yr old dmft > or = 2
