Fig. 4

Schematics and characterizations of biomineralization-inspired materials for dentin demineralization. (I) a TEM image of P26-collagen self-assembly. The assembled P26 peptides are dispersed nanospheres around the collagen fibril. b TEM image of collagen mineralization with P26 shows intrafibrillar mineralization and the inserted selected-area electron diffraction (SAED) image indicates the presence of HAP. Cross-sectional scanning electron microscopy (SEM) images of dentin after remineralization: c, d Control, and e, f with P26. By comparison, P26-treated dentin shows more apparent remineralization inside the dentinal tubules, which is reflected by a distinct string-of-beads morphology of the collagen fibrils. (II) a–d TEM images of ACP on collagen fibrils pretreated with different concentrations of citrate; a 0. b 25 × 10^–3 _M. c 50 × 10^–3 _M. d 100 × 10^–3 _M. These images indicate that citrate facilitates the infiltration of ACP into collagen fibrils. e Schematic of collagen mineralization via citrate pretreatment. Citrate decreases the contact angle and improves the wetting of ACP on collagen fibrils, and further promotes the degree of intrafibrillar mineralization. TEM images of remineralized dentin f without treatment and g with 100 × 10^–3 _M citrate treatment. By contrast, citrate significantly promotes dentin remineralization. Scale bars: 50 nm (a–d), and 1 μm (f, g). (I) was reproduced with permission from ref. ¹⁴⁵, 2020 American Chemical Society. (II) was reproduced with permission from ref. ¹³⁴, 2018 Wiley-VCH