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Decline in enamel hypoplasia in relation to fluoridation in Australians
1Department of Anthropology, Southern Illinois University, Carbondale, Illinois 62901-4502, USA. rcorrucc@siu.edu
Abstract:
Enamel hypoplasias are thought to represent calcification disruption indicative of metabolic stress during development. Hypoplasias of permanent maxillary central incisors and mandibular canines have undergone a notable reduction in frequency between Euro-Australian twins born around 1965 and those born ca. 1990. Even when scored very liberally these linear defects are 3.1-4.6 times as prevalent in the earlier Australians, and the discrepancy is proportionately greater among strictly scored defects. Likely correlates of this secular trend logically include reduced childhood fevers and clinical intervention to reduce circum-natal stresses acting on cotwins. However, fluoridation of metropolitan water has emerged as the statistically strongest hypoplasia-preventing factor.
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