Parner E T, Heidmann J M, Vaeth M, Poulsen S
Department of Biostatistics, University ofAarhus, 6 Vennelyst Boulevard, DK-8000 Arhus C, Denmark.
Arch Oral Biol. 2001 May;46(5):425-31. doi: 10.1016/s0003-9969(01)00002-4.
The purpose was: (1) to estimate mean eruption times of permanent teeth in Danish schoolchildren for the birth cohorts from 1969 to 1982; and (2) to determine any time trends in eruption. For teeth with a low proportion of aplasia, the distribution of the eruption time was close to normal. For teeth with a higher proportion of aplasia there was a slight deviation from the normal distribution in the right-hand part of the distribution. For erupted teeth, the time to eruption was, however, again very close to the normal distribution. A small, but statistically significant, increase in mean eruption times was found for both sexes and almost all teeth. Averaged over all teeth the increase was 1.5 days per year (95% CI: 0.9--2.2) for boys and 2.6 days per year (95% CI: 2.2--2.9) for girls.
