Figure 4.

Ability of electrospun nanofibers containing ACP to regenerate dentin structure, as revealed by TEM image (A). Dentin cross-section imaged after etching (B) and after treatment with hydrated ACP/PVP (C), showing occlusion of tubules (green arrows). Regeneration of enamel by self-assembling peptides, showing aligned HA crystals sectioned longitudinally (arrows) and in cross-section (arrowheads) (D), representing considerable resemblance to that of authentic enamel (E). Molecular models of designed peptides RADA16 and PRG (F) and the formation of the self-assembled nanofiber present a beta-sheet structure (G). Periodontal ligament fibroblasts cultured in collagen gel in the presence or absence of the functional peptide, showing the ability of cells to penetrate into the gel when the PRG sequences were present in the gel (H). (A–C) Adapted from Fletcher J, Dominic W, Emma Fowler C, Mann S. Electrospun mats of PVP/ACP nanofibres for remineralization of enamel tooth surfaces. Cryst Eng Comm. 2011;13:3692 with permission of The Royal Society of Chemistry.²¹⁹ (D and E) Adapted from Biomaterials, 31, Huang Z, Newcomb CJ, Bringas P Jr, Stupp SI, Snead ML, Biological synthesis of tooth enamel instructed by an artificial matrix, 9202–9211, Copyright © 2010, with permission from Elsevier.²⁰⁶ (F–H) Adapted from Kumada Y, Zhang S. Significant type I and type III collagen production from human periodontal ligament fibroblasts in 3D peptide scaffolds without extra growth factors. PLoS One. 2010;5:e10305.²⁰⁷

Abbreviations: ACP, amorphous calcium phosphate; TEM, transmission electron microscopy; PVP, poly(vinylpyrrolidone); HA, hydroxyapatite.