Does caries in primary teeth predict enamel defects in permanent teeth? A longitudinal study.

The notion that caries in primary teeth causes developmental defects of enamel in permanent teeth has been recently revived. The research objective was to test this hypothesis through analysis of data from the Dunedin Multidisciplinary Health and Development Study, a longstanding prospective cohort study. The maxillary incisors of 663 children were assessed for existing restorations and dental caries at age five and for developmental defects of enamel at age nine. Where a primary tooth had been carious, the permanent successor was more likely to have a demarcated opacity after adjustment for gender, family socio-economic status, years of exposure to water fluoridation, trauma to primary teeth, and early loss of primary teeth (unadjusted OR = 2.3, 95% CI 1.3, 4.1; adjusted OR = 2.2, 95% CI 1.1, 4.3). These findings support a time-ordered association between dental caries in primary maxillary incisors and demarcated opacities in their permanent successors.