Abstract
Since the 1950s, the benefits and risks of fluoridated water use have been debated worldwide. In the past, it was considered that the systemically ingested fluoride would exert its primary preventive effect after being incorporated into the enamel as fluorapatite, making the enamel more resistant to the caries process; however, it is now recognized that the main effect of water fluoridation is local and post eruptive. On the other hand, irrespective of the caries decline reported worldwide, the anticaries benefit of water fluoridation continues to be observed even in developed countries. Regarding the risks, water fluoridation is considered an acceptable community-based method for fluoride delivery, because the risk of developing dental fluorosis lesions due to the ingestion of fluoride during the enamel formation period has been deemed acceptable when contrasted to the anticaries benefits of fluoride. However, the use of fluoride in water to control caries has created a controversy due to data associating water fluoridation as the cause of some systemic diseases. Therefore, the aim of this descriptive review was to discuss the systemic effects (risks) of water fluoridation use.
Excerpts
Figure 4 Prevalence of dental fluorosis in Brazil, according to SB 2010 (Brazilian Ministry of Health, 2010 national oral health survey) 16.
Table 5 Chronology of campaigns against water fluoridation and allegations used (modified from Newbrun, 1996).
| Year | Allegations |
| 1950 | Communist plan |
| 1960 | Toxic waste, polluting |
| 1970 | Government conspiracy |
| 1980 | Industrial interests, cancer in humans, |
| Aging, Alzheimer’s disease | |
| 1990 | AIDS, bone fracture, birth rate |
| 2000-present | Decreased IQ, hypothyroidism |
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