Bioinspired mineral-in-shell nanoarchitectonics: Functional empowerment of mineral precursors for guiding intradentinal mineralization

Effective mineralization of biological structures poses a significant challenge in hard tissue engineering as it necessitates overcoming geometric complexities and multistep biomineralization processes. In this regard, we propose “mineral-in-shell nanoarchitectonics”, inspired by the nanostructure of matrix vesicles, which can influence multiple mineralization pathways. Our nanostructural design empowers mineral precursors with tailorable properties through encapsulating amorphous calcium phosphate within a multifunctional tannic acid (TA) and silk fibroin (SF) nanoshell. The bioinspired nanosystem facilitates efficient recruitment of mineral precursors throughout the dentin structures, followed by large-scale intradentinal mineralization both in vitro and in vivo, which provides persistent protection against external stimuli. Theoretical simulations combined with experimental studies attribute the success of intradentinal mineralization to the TA-SF nanoshell, which exhibits a strong affinity for the dentin structure, stabilizing amorphous precursors and thereby facilitating concomitant mineral formation. Overall, this bioinspired mineral-in-shell nanoarchitectonics shows a promising prospect for hard tissue repair and serves as a blueprint for next-generation biomineralization-associated materials.