Dynamically customizable 4D printed shape memory polymer biomedical devices: a review

Abstract There is an increased risk of complications and even surgical failures for various types of medical devices due to difficult to control configurations and performances, incomplete deployments, etc. Shape memory polymers (SMPs)-based 4D printing technology offers the opportunity to create dynamic, personalized, and accurately controllable biomedical devices with complex configurations. SMPs, typical representatives of intelligent materials, are capable of programmable deformation in response to stimuli and dynamic remodeling on demand. 4D printed SMP medical devices not only enable active control of configuration, performance and functionality, but also open the way for minimally invasive treatments and remote controllable deployment. Here, the shape memory mechanism, actuation methods, and printing strategies of active programmable SMPs are reviewed, and cutting-edge advances of 4D printed SMPs in the fields such as bone scaffolds, tracheal stents, cardiovascular stents, cell morphological regulation, and drug delivery are highlighted. In addition, promising and meaningful future research directions for 4D printed SMP biomedical devices are discussed. The development of 4D printed SMP medical devices is inseparable from the in-depth cooperation between doctors and engineers. The application of 4D printed SMP medical devices will facilitate the rapid realization of ‘smart medical care’ and accelerate the process of ‘intelligentization’ of medical devices.