Iron Oxide-Based Magnetic Nanoparticles in Oral Infection Control

In oral infectious diseases, recalcitrant biofilms, escalating antibiotic resistance, and limitations of local drug delivery within complex anatomical microenvironments necessitate innovative strategies for effective and precise therapy. Among magnetic nanoparticles (MNPs), iron oxide-based nanoparticles (IONPs) have attracted considerable attention in the management of oral infectious diseases because of their unique physicochemical features, including magnetic responsiveness, tunable morphology, and favorable biocompatibility. These properties enable MNPs to exert multimodal antibacterial effects, such as biofilm disruption, magnetothermal therapy, and reactive oxygen species (ROS)-mediated bactericidal activity, thereby allowing them to adaptively target and act within the anatomically constrained, biofilm-rich infection sites of the oral cavity. Recent advances have further explored their applications in caries, endodontic and periapical infections, periodontitis, peri-implantitis, and osteomyelitis of the jaw, highlighting their potential to overcome the limitations of conventional antibiotics. MNPs also enable rapid detection of oral pathogens via magnetic enrichment and point-of-care platforms, complementing their therapeutic potential. Key challenges include complex oral microenvironment interference, uncertain long-term biocompatibility, and obstacles to clinical translation. Future directions focus on omics-guided optimization, theranostic platforms integrating imaging and targeted therapy, and microbiota-modulating strategies. This review provides a comprehensive overview of the antibacterial mechanisms, therapeutic applications, and emerging multifunctional platforms of MNPs in oral infection control, while highlighting their translational potential and supporting their advancement toward safe and effective clinical applications.