Material extrusion techniques for biomedical applications: Biomaterials and their performance – A review

Material extrusion-based additive manufacturing (AM) is transforming the medical sector by enabling innovative, cost-effective, and highly customizable solutions. This review examines key material extrusion methods, namely Fused Filament Fabrication (FFF), Direct Ink Writing (DIW), and Direct Pellet Extrusion (DPE), highlighting their advantages, material versatility, and medical applications. These technologies support the development of personalized implants, prosthetics, tissue engineering, scaffolds, and drug delivery systems (DDS). A broad range of materials, like thermoplastics (e.g., PCL, PLA, PEEK), hydrogels (e.g., alginate, collagen), metals (e.g., titanium alloys), and bioceramics (e.g., hydroxyapatite, zirconia), influence mechanical properties, biocompatibility, and degradation behavior. Thermoplastics provide durability, hydrogels promote cell growth, and bio ceramics aid bone regeneration. However, challenges like material limitations, mechanical strength, and degradation control require further research. Developments in composite printing, hybrid systems, and precision engineering are improving resolution, speed, and scalability. Innovations in smart polymers, nanocomposites, and bioactive hydrogels enhance functionality, while AI and robotics optimize design and fabrication. Despite these developments, regulatory and ethical concerns regarding safety and accessibility must be addressed. Future progress in custom organ printing and biodegradable implants holds promise for personalized healthcare, emphasizing the need for interdisciplinary collaboration to realize the full capabilities of material extrusion-based AM in medicine.