Collaborative Research: Developmental links between teeth and faces

Slippery Rock University Of Pennsylvania, Slippery Rock PA

Investigators

Abstract

Faces transform from birth to adulthood. Growing and erupting teeth are among the most transformative drivers of changes in facial appearance, promoting bone formation and influencing overall jaw growth. Prior research has focused on the eruption of ‘baby teeth’, or deciduous teeth, and subsequent permanent teeth. However, the period near or at birth, when many teeth are not yet fully developed, has rarely been studied. This study investigates the role(s) of teeth in facial development during early critical periods, and results inform a better understanding regarding how different parts of anatomy can influence the appearance of others, as well as the whole organism. The project generates 3D models, a website and other resources for K-12 students and provides training and professional development to one postdoctoral scholar and multiple graduate and undergraduate students. This study investigates the underpinnings of functional matrix theory, which posits that bones that border soft tissue structures and other organs such as teeth, directly cause transformations of bone morphology. The principal investigators use the two sides of lower jaw to study cellular and tissue-level event in tooth and jaw formation, which are then mirrored on three-dimensional reconstructions of the opposite side of the jaw. The three-dimensional reconstructions are accomplished using micro computed tomographic (µCT) scanning to detect bone, following by a second scan after soaking half of the jaw in iodine, after which unmineralized tooth germs are easily detectable using µCT. Amira software are used to generate three-dimensional views that denote critical cellular and tissue-level mechanisms (i.e., cell signals for bone deposition and resorption, and bone cell maturation). µCT will also be used for morphometric analyses. Ultimately, by investigating how developing teeth compete for space within a growing face, results are relevant for interpreting variation in modern and past anatomy. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.