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An epidemiological comparison of Dean's index and the Developmental Defects of Enamel (DDE) index
A Rizan Mohamed1, W Murray Thomson, Timothy D Mackay
1Ministry of Health, Brunei Darussalam.
Objectives:
To compare the Dean's and DDE indices in examining dental fluorosis and diffuse opacities.
Methods:
Survey of a random sample of 9-year-old children in Southland, New Zealand. Dental fluorosis was measured using Dean's index. Enamel defects were recorded using the DDE index.
Results:
A total of 436 children (74.5 percent) were examined: 24.1 percent had diffuse opacities, and 10.8 percent of children had fluorosis (P < 0.001). At tooth level (using the score for the same tooth), the indices were more similar, but 9 percent of the 33 with diffuse opacities showed no visible signs of fluorosis.
Conclusions:
We found relatively little concordance between the DDE and Dean's indices in determining person prevalence of defects among children. At the tooth level, concordance between the two was greater, and suggests that little maybe lost in fluorosis studies which use the DDE index, particularly as it enables collection of a wider and more comprehensive range of information. Although the use of Dean's index is important for historical comparisons, investigators should appreciate its limitations.
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