All-in-One Nanounit Embedded with Biomimetic Peptide for Comprehensive Caries Repair.

Dental caries at varying stages exhibits diverse microstructural damage in dental hard tissues and complex restorative needs. A key challenge lies in developing therapeutic materials capable of reversing multitype damage, including inorganic mineral loss, organic collagen demineralization, and pulpal irritation, while anchoring to differentiated enamel-dentin-pulp interfaces for multitissue repair. Herein, a simplified "all-in-one" biomimetic strategy inspired by the biomineralization microenvironment during tooth development is proposed, constructing QP5/ACP@MSN (MQA) nanounit for caries repair. This nanounit incorporates two pivotal modulators in biomineralization: the amelogenin-derived peptide QP5 as a thread-like regulator and amorphous calcium phosphate (ACP) as a mineral source. Through the orchestrated coordination of QP5 and ACP, MQA achieves efficient anchoring to residual hydroxyapatite in carious tissues. In vitro, it promotes biomineralization of enamel and dentin and odontogenic differentiation of pulp cells. In vivo, it demonstrates prevention-restoration-regeneration effects under highly cariogenic environment in a rat caries model. As a functional unit, MQA provides mineralization guidance, mineral supply, and pulp cell activation. As a structural unit, MQA self-assembles onto substrates to provide versatile applications for various intraoral tissue interfaces. This study introduces a unified solution for multitype and multitissue caries repair, while offering strategic inspiration for repairing lesions with complex tissue damage.