The Emerging 4D Printing of Shape‐Memory Thermomorphs for Self‐Adaptative Biomedical Implants

Abstract Shape‐memory thermomorphs (SMTMs) are materials that undergo morphological changes when subjected to external heat stimulation. The rapid evolution of additive manufacturing has significantly propelled advancements in SMTM research and its potential applications. The combination of SMTMs with additive manufacturing has played a pivotal role in the rapid development of 4D printing, a transformative approach that introduces the temporal evolution of shape over time. This innovative synergy has given rise to a myriad of biomedical implants characterized by high structural complexity and remarkable self‐adaptability, marking substantial progress in recent years. The primary objective of this review is to provide a comprehensive overview of the burgeoning subfield by delving into the materials development, underlying mechanisms, shape programming methods, and the pivotal role of heat as a stimulus. Heat stimulation methods are examined in depth, and categorized into contact and remote heating approaches, with their mechanism, effects, and practical implementations elucidated. Furthermore, the most prominent application of this field, namely self‐adaptative biomedical implants, is highlighted with recent breakthroughs and innovations domenstrated. Lastly, the prospects and challenges that lie ahead are analyzed, providing valuable insights for researchers to continue propelling the progress of this transformative technology.