A one-step additive for dental 3D-printed PMMA resins: Green-synthesized AgNP-doped PVP nanofibers confer mechanical, antifungal, and aesthetic advantages.

The application of 3D manufacturing techniques in dentistry holds significant potential for the fabrication of dental components, such as prosthetic bases. However, 3D-printed polymethyl methacrylate (PMMA) resins often exhibit inferior mechanical strength and a higher susceptibility to Candida albicans biofilm adhesion compared to conventional materials. This study addresses these limitations by developing a novel composite material. We integrated green-synthesized silver nanoparticles (AgNPs), using Thymus sp. extract, into polyvinylpyrrolidone (PVP) nanofibers via electrospinning. These AgNP/PVP nanofiber mats were then incorporated into 3D-printed PMMA resin. Comprehensive characterization through different techniques confirmed successful AgNP synthesis and their homogeneous distribution within the nanofiber matrix. This study was the first to show that PVP nanofibers formed a uniform dispersion of short fragments within the PMMA resin as shown by the Field Emission Scanning Electron Microscopy (FESEM) results. Mechanical testing revealed that the AgNP/PVP nanofiber composites significantly enhanced the flexural strength of PMMA, while AgNPs alone adversely affected mechanical properties. Biological evaluation demonstrated remarkable dose-dependent antifungal activity against C. albicans. The Resin/PVP sample showed 2.04% inhibition, while the Resin/AgNP formulation was significantly more effective with 33.30% inhibition. The three Resin/PVP-AgNP composites exhibited inhibition rates, ranging from 13.17% to 16.10%. Although increased AgNP concentration influenced color parameters, the PVP matrix effectively prevented clinically unacceptable discoloration. The synergistic combination of green-synthesized AgNPs with PVP nanofibers presents a promising multifunctional solution for 3D-printed dental resins, simultaneously addressing mechanical durability, antimicrobial protection, and aesthetic requirements in clinical applications.