Nanotechnology in Dental Restorative Materials: Advances, Challenges, and Future Directions Toward Precision Nanomedicine

Background: Nanotechnology has reshaped dental materials by enabling nanoscale control of composition and interfaces, yielding surface-dominated reactivity and bioactive functions that can outperform conventional restoratives. However, routine clinical translation remains limited, and precision applications are still emerging. This review examines synthesis principles and their integration into restorative materials, emphasizing performance gains, limitations, and future opportunities. Main body: A narrative synthesis was conducted integrating fundamental nanoscience, synthesis strategies (top-down, bottom-up, green or bio-inspired, hybrid, and emerging microfluidic, laser-assisted, and nanomaterial-enabled additive manufacturing routes), and evidence across ceramics, resin composites, glass ionomer cements, dental adhesives, denture base resins, and 3D-printing polymers. Reported benefits arise from mechanisms such as nanofiller-mediated crack deflection, densification and microstructural refinement, improved optical behavior through reduced light scattering, and therapeutic activity via ion release, photocatalysis, and bioactive interfacial mineralization. Applications include nanostructured ceramics for improved toughness, nanofilled composites for durability and esthetics, nanoparticle-modified glass ionomers with strengthened matrices and antibiofilm activity, and bioactive adhesives that support antimicrobial action and calcium phosphate based remineralization. Persistent barriers include nanoparticle agglomeration, dispersion and viscosity trade-offs, batch-to-batch variability, long-term hydrolytic or thermal aging instability, incomplete biosafety datasets, and regulatory and scale-up constraints. Conclusion: Nanotechnology is moving restorative dentistry from passive replacement toward multifunctional, safer, and patient-adaptable materials. Advancing toward precision nanomedicine will require standardized synthesis and characterization, scalable manufacturing, rigorous toxicology, and longitudinal clinical trials, together with greener synthesis and smart, stimuli-responsive systems integrated into digital workflows such as (three-dimensional) 3D printing.