Prevalence of developmental defects of enamel and dental caries in New Zealand children receiving differing fluoride supplementation.

A survey of the prevalence of dental caries and developmental enamel defects in 666 New Zealand children aged 9 years and with differing histories of fluoride supplementation was carried out in 1982. In the LF (low fluoride) group 22.8% of children had diffuse white opacities compared with the WF (water fluoridation) group, 36.7%, and the CT (continuous use of fluoride tablets) group 49.4% (P = 0.0018). When the tooth prevalence was determined, the differences were more marked with 4.9% of teeth affected in the LF group and 24.7% in the CT group. Dental caries prevalence in the fluoride history groups displayed an inverse relationship with fluoride supplementation, the LF group had a DMFT of 2.4, the WF group, 1.7 and the CT group, 1.2. The prevalence of both diffuse opacities and of dental caries in the PT group where tablets had been used to 5-6 yr of age was anomalous. The survey confirmed that diffuse opacities occur in children with a low fluoride intake but the prevalence increases in groups of children given fluoride supplements.