Figure 2.

Hierarchical architecture of mammalian enamel. Enamel (E) is the outermost layer at the crown of the tooth and resides above the dentin (D). The pulp (P) contains nerves and blood vessels, while the cementum (C) is the outermost layer of mineralized tissue surrounding the root of the tooth allowing the tooth to be anchored to the jawbone through the periodontal ligament (PDL). The bulk image depicts the enamel organ, the transition across the dentin–enamel junction, and the dentin below. On the mesoscale level, prismatic enamel consisting of weaving of rods (or prisms) that range from 3 to 5 μm in diameter can be visualized. Upon further magnification, the micrometer scale shows the composition of a single rod. The nanometer scale reveals a highly organized array of individual HA crystallites (~30 nm thick, 60 nm wide, and several millimeters in length), which are preferentially aligned along the c-axis.

Copyright (c) 2008, MRS Bulletin Reproduced with permission from Tamerler C, Sarikaya M. Molecular biomimetics: genetic synthesis, assembly, and formation of materials using peptides. MRS Bull. 2008;33(5):504–510.