EFFECT OF EARLY OR LATE ERUPTION OF PERMANENT TEETH ON CARIES SUSCEPTIBILITY

Objectives: The aim of this study was to analyse the possible effect o f early or late eruption of permanent teeth on the placement of first restorations on the different surfaces. The oral health records, of a total of 486 children born in 1970 and 1971 living in three rural comm unities in Finland, were analysed. Methods: Caries susceptibility was determined indirectly by a new method. The study groups were defined a s falling outside one standard deviation either side of the mean value for the timing of the eruption of first permanent molar teeth. Result s: No statistically significant differences in restoration increments between the early and late eruption cohorts were found at the end of t he study period. For the occlusal surfaces of the first molar teeth, t he restoration placement curves plateaued at about 60-70%, while for t he second molar teeth, the plateaus occurred at 50-60% for both study cohorts. In girls with 'late eruption', the height of the post-eruptiv e step (i.e. the number of teeth filled on the year of their eruption) was higher (50-100%) compared to boys and girls with 'early eruption' . The difference was statistically significant. For example, for the o cclusal surface of D. 36, the 95% confidence interval for the differen ce between proportions was 12-53%. Conclusion: No consistent effect of early or late eruption of permanent teeth was found on caries suscept ibility measured post-eruptively by the placement rate of first restor ations in a follow-up study of more than 10 years among Finnish childr en born in 1970-1971. Copyright (C) 1996 Published by Elsevier Science Ltd.