Hollow ZIF-8 nanoparticles Delivering PAH-ACP for multifunctional dentin Repair: Simultaneous Remineralization, antibacterial Activity, and Odontoinduction

• Hollow ZIF-8 loaded with PAH-ACP for adhesive interfaces. • Induction of the intrafibrillar mineralization of collagen fibrils. • Robust antibacterial activity and enhanced odontoinductive activity. • Demonstrates promising applications in adhesive dentistry and biomaterial design. Resin-bonded restorations, a prevalent treatment modality for dental defects, are prone to complications including nanoleakage, secondary caries, and pulpal pathology over extended service periods. To address these challenges, this study developed a multifunctional biomaterial, HZN@PAH-ACP, specifically designed for application at the dentin bonding interface. The material was fabricated by etching ZIF-8 with tannic acid to produce HZN, which was subsequently loaded with poly(allylamine)-stabilized amorphous calcium phosphate (PAH-ACP). The structure and formation mechanism of this biomaterial were thoroughly investigated using electron microscopy and molecular dynamics simulations. Meanwhile, HZN@PAH-ACP effectively induced intrafibrillar mineralization of collagen fibers and promoted remineralization of demineralized dentin, significantly reducing nanoleakage within the hybrid layer. Furthermore, the material inhibited the activity of Streptococcus mutans and exhibits excellent biocompatibility, while simultaneously enhancing the odontogenic differentiation and mineralization of human dental pulp stem cells. All powered by the simultaneous release of calcium, phosphate, zinc ions, and tannic acid, and the reduction in pH further accelerates this process. The development of this biocompatible, multifunctional repair biomaterial presents considerable clinical potential, as it addresses multiple challenges concurrently through a single application, that can be used in adhesive primers and pulp capping agents, offering a promising solution for dental restoration.