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Systemic Fluoridation and Fluoride Toxicity
Systemic Fluoridation
- Water fluoridation.
- Fluoride tablets and drops.
- Fluoridated milk.
- Fluoridated salt.
Water Fluoridation
Water fluoridation is the controlled adjustment of the natural fluoride concentration in drinking water to that recommended for optimal dental health. The optimum level of fluoride in drinking water was determined as 1 mg/l (1 ppm) from the original 21 cities study of Dean in 1942. Water fluoridation is effective at reducing caries by about 50% (York Review) and has been hailed as one of the 10 greatest achievements in public health in the twentieth century. It is socially equitable, in that it is available to all social groups and ages. With the exception of dental fluorosis, no association between adverse effects and water fluoridation has been established. The development of dental fluorosis is influenced by the total fluoride ingestion from all sources, including toothpaste, during tooth development. Approximately 300 million people drink fluoridated water worldwide. It is not more widespread due to political issues and the anti-fluoride lobby. Cessation of water fluoridation has been shown to lead to increased caries to pre-fluoridation levels within 5 years. In recent years, the use of bottled drinking waters has become more extensive and their fluoride levels may play a role in caries prevention.
Fluoride Tablets and Drops
Fluoride tablets and fluoride drops (traditionally termed fluoride supplements) were intended to mimic the consumption of fluoride from naturally fluoridated water. Now the common view is that it is through the topical effect on tooth surfaces that fluorides have a caries preventive action and the term “supplements” should be avoided. As the systemic effect of fluoride plays a more minor role in caries inhibition it may be argued that fluorides should be applied locally and not given systemically. The dosage of fluoride tablets and drops varies worldwide and the major drawback of their use is the very poor patient compliance. This explains the wide variation in reported caries reductions with supervised studies having the greatest caries reductions. When used the maximum dose should be 0.5 mg daily and patients should be advised to allow the tablets to dissolve slowly whilst moving the tablet around the mouth so that all teeth benefit from the topical effect of the />