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A controlled study of risk factors for enamel hypoplasia in the permanent dentition
D Ford1, W Kim Seow, S Kazoullis
1Northside Specialist Centre, Alderley, Queensland, Australia
Purpose:
The purpose of this study was to investigate risk factors for enamel hypoplasia (EH) and enamel opacity (EO) in the permanent teeth of healthy schoolchildren from a nonfluoridated community in Australia.
Methods:
Children with EH (N=104) or EO (N=104) were compared with matched controls without enamel defects (N=105). Subjects who previously resided in on optimally fluoridated town provided data on the effects of drinking fluoridated water.
Results:
The main risk factors for EH were low socioeconomic status (P < .04), respiratory infections (P < .001), exposure to cigarette-smoking (P = .001), asthma (P = .007), otitis media (P = .01), urinary tract infection (UTI; P = .03) and chickenpox (P = .001). Combinations of either chickenpox and UTI or chickenpox and exposure to cigarette-smoking were associated with relatively high numbers of EH. While use of adult toothpaste (1000 ppm) at 0 to 3 years old increased risks for EH, there were less EO in children who used child toothpaste (300 ppm fluoride, 86% vs. 95%; P = .02) or who drank optimally fluoridated water compared to those who did not (4% vs. 29%; P < .001).
Conclusions:
Children with low socioeconomic status, histories of respiratory or chickenpox infections, exposure to cigarette-smoking, urinary tract infections, otitis, and use of adult toothpaste are predisposed to enamel hypoplasia. By contrast, drinking optimally fluoridated water at 0 to 3 years old reduces the risk for enamel opacities.
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