Enabling Real‐Time, Non‐Ionizing 3D Imaging of Implantable Magnetic Cements Using Magnetic Particle Imaging

Abstract Magnetic Particle Imaging (MPI) is a non‐ionizing tomographic technique capable of real‐time 3D imaging with unmatched temporal resolution, reaching up to 46 vol/s. These features make MPI a promising tool for the monitoring of implantable resin composites, particularly in scenarios requiring frequent safe, and dynamic assessment. However, integrating magnetic responsiveness into medical materials without compromising their structural and biological integrity remains a challenge. In this study, it is presented the first strategy to enable MPI signal generation in a commercial implantable cement by depositing a continuous iron thin film onto its surface. This structured magnetic layer introduces directional magnetic anisotropy, resulting in an angle‐dependent MPI signal. This directional dependence can be explored to noninvasively track for the position and orientation of the implant, potentially benefiting applications in confined anatomical regions. In vitro assays confirmed that the incorporation of the magnetic layer does not compromise cytocompatibility. Altogether, these findings demonstrate that magnetic thin films can serve as anisotropic contrast sources for MPI, expanding the range of new possibilities for imaging implantable materials with orientation‐sensitive contrast and without ionizing radiation.