Dental or enamel fluorosis

The primary adverse effects associated with chronic, excess fluoride intake are skeletal, and dental or enamel, fluorosis. Other effects, including hypersensitivity reactions, renal insufficiency, immunological effects, possible association with repetitive strain injury, birth defects and cancer have been observed and discussed [17,41-45]. 

Dental or enamel fluorosis is an irreversible dose-response effect caused by fluoride ingestion during the pre-eruptive development of teeth. The pre-eruptive maturation of crowns of the anterior permanent teeth, which are of most concern aesthetically, is complete and, together with the risk of fluorosis, is over by the age of 7-8 years [46,47]. After the enamel has completed its pre-eruptive maturation, it is no longer susceptible. Therefore, fluoride intake up to the age of 7-8 years is of most interest. Although it is usually the permanent teeth that are affected, occasionally the deciduous teeth may be also involved. 

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