Dentin remineralization induced by nanobioactive glass in association with RGDS peptide

The aim of this study was to investigate the binding ability of a arginine-glycine-aspartate-serine (RGDS) peptide to dentin and its effect on the dentin remineralization, dentin cohesive strength and intrafibrillar mineralization induced by nanobioactive glass (nBG). The demineralized dentin discs were treated with RGDS and/or nBG and then incubated in stimulated body fluid for 2 weeks. The results of scanning electron microscopy, energydispersive X-ray spectroscopy, X-ray diffraction and confocal laser scanning microscopy showed that RGDS could bind to dentin and promote the attachment of nBG. Compared to the nBG group, the RGDS + nBG group induced more apatite formation on the dentin surface and apatite rods inside the dentinal tubules. The results of transmission electron microscopy showed crystal lattice formation in the demineralized dentin matrix treated with nBG or RGDS + nBG, indicating the remineralization of dentin. The RGDS + nBG-treated dentin had the highest dentin cohesive strength in all groups. The self-assembled collagen fibrils exposed to RGDS + nBG exhibited intrafibrillar mineralization. In conclusion, RGDS promoted nBG-induced apatite formation and dentin collagen matrix remineralization, thus enhancing the dentin strength. The results lay a foundation for the wide application of RGDS and nBG in dentin erosion, dentin hypersensitivity, dentin bonding interface improvement, and regenerative dentistry.