Childhood variation in skeletal and dental development

Abstract

The existing research comparing variation in developmental timing of skeletal and dental systems has focused on cross-sectional correlations of group means throughout late childhood. We used a longitudinal sample of 100 White American girls to compare developmental variation from 3-12 years to improve our understanding of developmental variation. The sample was divided into two sets (dental and skeletal) of three subgroups (delayed, average, or advanced) based on development at age three. Repeated measure ANOVA and Tukey’s HSD analyses examined the longitudinal maturation of: 1) skeletal development of skeletal subgroups, 2) dental development of skeletal subgroups, 3) dental development of dental subgroups, and 4) skeletal development of dental subgroups. The four models demonstrated significant differences between subgroup developmental trajectories. Pairwise comparisons of same-system development (analyses 1 and 3) found all comparisons to be significant; this was not the case for pairwise comparisons across systems (analyses 2 and 4). Only the advanced group was consistently different across all combinations. Results suggest that the pace of development differs among delayed, average, and advanced individuals, and between dental and skeletal systems. Therefore, to fully explore the relationship between the systems, the full range of variation in the timing of development is required.