Three-Dimensional Bolton–Brush Growth Study Landmark Data: Ontogeny and Sexual Dimorphism of the Bolton Standards Cohort

Abstract

Simultaneous frontal and lateral anatomic landmark identification improves three-dimensional localization reliability. Three-dimensional craniodental shape change from ages 8 to 18 within the Bolton standards presents little heterogeneity. Considerations of ethnicity aside, these may be initial grounds for use of these data as a normative referent.

Surface-bounded growth modeling applied to human mandibles

“…The present study does not reject that hypothesis, but indicates that the growth is linear if modeled in Procrustes space. This also complies very well with the result of [16]. A combination of the two "frames" might be very fruitful.…”

“…No patient controls the variability of the pooled analysis. Other computations, not shown here, confirm the observation, first set out in [16], that removing variation of patients' mean shape greatly enhances the reliability of the resulting PCA analysis of growth per se. Because patient 's scans are already aligned with the grand mean shape, a new shape may be modeled by (10) where is a growth index parameter and is one of patient 's earlier forms.…”

“…The present work has been greatly inspired by the seminal work of Cootes and colleagues ( [15] for an overview) and Dean et al [16] (see below). Manually detected landmarks have been used for Cootes and colleagues' analysis [15].…”

“…11, it appears that the three to seven forms of each case lie reasonably close to a line in Procrustes space. We can, thus, summarize each by its own first principal component [16], and then examine the resulting six vectors to see how they may be ordinated. Fig.…”

Heterochrony and geometric morphometrics: a comparison of cranial growth in Pan paniscus versus Pan troglodytes

“…In geometric morphometrics, principal component analysis (PCA), which is called relative warp analysis when applied to Procrustes coordinates (Bookstein 1991;Rohlf 1993), has become the standard tool for the analysis of ontogeny and phylogeny (see e.g., O'Higgins and Jones 1998; Dean et al 2000;O'Higgins 2000a, b;O'Higgins et al 2001;Ponce de Le´on and Zollikofer 2001;Ackermann and Krovitz 2002). However, identity of position or direction between different growth trajectories in a PCA has to be examined with care.…”