A post-classical theory of enamel biomineralization… and why we need one

Abstract

Genetic research into tooth-enamel formation reveals a mineralization front along which crystals form, US and Canadian scientists report. James P. Simmer and colleagues at the University of Michigan, USA, and McGill University, Canada, reviewed recent genetic studies which suggest that enamel formation, or amelogenesis, is closely linked to the activity of ameloblasts, the cells that initiate tooth growth. Based on laboratory studies, the classical theory of amelogenesis describes crystal growth on an extracellular matrix with mineral deposition governed by proteins. However, enamel appears to behave differently within the body. Studies on rodents suggest that the first mineral present in enamel is amorphous calcium phosphate (ACP), and that the initial enamel ribbons are not crystalline but flexible. A mineralization front, sustained by the ameloblast cell membrane, shapes and orientates the ribbons before they harden into rod-shaped crystals.

Keywords

ameloblastin / amelogenin / enamelin / mineralization front / tooth

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