Central airway obstruction is a life-threatening disorder causing a high physical and psychological burden to patients. Standard-of-care airway stents are silicone tubes, which provide immediate relief but are prone to migration. Thus, they require additional surgeries to be removed, which may cause tissue damage. Customized bioresorbable airway stents produced by 3D printing would be highly needed in the management of this disorder. However, biocompatible and biodegradable materials for 3D printing of elastic medical implants are still lacking. Here, we report dual-polymer photoinks for digital light 3D printing of customized and bioresorbable airway stents. These stents exhibit tunable elastomeric properties with suitable biodegradability. In vivo study in healthy rabbits confirmed biocompatibility and showed that the stents stayed in place for 7 weeks after which they became radiographically invisible. This work opens promising perspectives for the rapid manufacturing of the customized medical devices for which high precision, elasticity, and degradability are sought.

Since the first report of 3D printed biodegradable structures by stereolithography, vat photopolymerization has shown great potential in the fabrication of medical implants and devices. Despite its superior printing quality and manufacturing speed, the development of biodegradable devices by this technique remains challenging. This results from the conflicting viscosity requirements for the printing resins, i.e., low viscosity is required for highresolution 3D printing, whereas high viscosity is often needed to provide high mechanical strength. Recently emerging photopolymerization-based 3D printing techniques, including heat-assisted digital light processing (DLP) and volumetric printing, have brought new hope to the field. With its tolerance to high viscosity resins, heat-assisted DLP enables the fabrication of complex, personalizes architectures from biodegradable photopolymers that are not printable by conventional printing techniques. On the other hand, volumetric printing, which abandons the layer-by-layer printing principle and thus circumvents the dependence on low viscosity resins, could be highly beneficial for the 3D printing of biodegradable devices. This perspective evaluates the key challenges associated with biodegradable photopolymers used in the 3D printing of medical implants and devices. One focuses on their chemical structures and physical properties and discusses future directions offered by these emerging techniques.

Central airway obstruction is a life-threatening disorder causing a high physical and psychological burden to patients due to severe breathlessness and impaired quality of life. Standard-of-care airway stents are silicone tubes, which cause immediate relief, but are prone to migration, especially in growing patients, and require additional surgeries to be removed, which may cause further tissue damage. Customized airway stents with tailorable bioresorbability that can be produced in a reasonable time frame would be highly needed in the management of this disorder. Here, we report poly(D,L lactide-co-ε-caprolactone) methacrylate blends based biomedical inks and their use for the rapid fabrication of customized and bioresorbable airway stents. The 3D printed materials are cytocompatible and exhibit silicone-like mechanical properties with suitable biodegradability. In vivo studies in healthy rabbits confirmed biocompatibility and showed that the stents stayed in place for 7 weeks after which they became radiographically invisible. The developed biomedical inks open promising perspectives for the rapid manufacturing of the customized medical devices for which high precision, tuneable elasticity and predictable degradation are sought after.

Vat photopolymerization 3D printing provides new opportunities for the fabrication of tissue scaffolds and medical devices. However, for the manufacturing of biodegradable elastomers, it usually requires the use of organic solvents to dissolve the solid photoinitators and achieve low resin viscosity, making this process environmentally unfriendly and not optimal for biomedical applications. Here, we report solvent-free 3D printing of biodegradable elastomers by digital light processing with well-defined photoinitiator–polymer conjugates. Being in liquid state at room temperature, the macrophotoinitiators enabled high-quality 3D printing in the absence of any organic solvents that are usually used in digital light 3D printing. This allowed the systematic investigation of structure–property relationships of 3D-printed biodegradable elastomers without the interference from reactive diluents. The developed macrophotoinitiators were compatible with various photopolymers and could be applied for solvent-free fabrication of biodegradable shape-memory devices. This work offers new perspectives for the solvent-free additive manufacturing of bioresorbable medical implants and other functional devices.

Digital light processing (DLP) 3D printing is a promising technique for the rapid manufacturing of customized medical devices with high precision. To be successfully translated to a clinical setting, challenges in the development of suitable photopolymerizable materials have yet to be overcome. Besides biocompatibility, it is often desirable for the printed devices to be biodegradable, elastic, and with a therapeutic function. Here, a multifunctional DLP printed material system based on the composite of gold nanorods and polyester copolymer is reported. The material demonstrates robust near‐infrared (NIR) responsiveness, allowing rapid and stable photothermal effect leading to the time‐dependent cell death. NIR light‐triggerable shape transformation is demonstrated, resulting in a facilitated insertion and expansion of DLP printed stent ex vivo. The proposed strategy opens a promising avenue for the design of multifunctional therapeutic devices based on nanoparticle–polymer composites.

The 3D printing of biodegradable elastomers with high mechanical strength is of great interest for personalized medicine, but rather challenging. In this study, we propose a dual‐polymer resin formulation for...

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Digital light processing (DLP) of structurally complex poly(ethylene glycol) (PEG) hydrogels with high mechanical toughness represents a long‐standing challenge in the field of 3D printing. Here, we report a 3D printing approach for the high‐resolution manufacturing of structurally complex and mechanically strong PEG hydrogels via heat‐assisted DLP. Instead of using aqueous solutions of photo‐crosslinkable monomers, PEG macromonomer melts were first printed in the absence of water, resulting in bulk PEG networks. Then, post‐printing swelling of the printed networks was achieved in water, producing high‐fidelity 3D hydrogels with complex structures. By employing a dual‐macromonomer resin containing a PEG‐based four‐arm macrophotoinitiator, “all‐PEG” hydrogel constructs were produced with compressive toughness up to 1.3 MJ m−3. By this approach, porous 3D hydrogel scaffolds with trabecular‐like architecture were fabricated, and the scaffold surface supported cell attachment and the formation of a monolayer mimicking bone‐lining cells. This study highlights the promises of heat‐assisted DLP of PEG photopolymers for hydrogel fabrication, which may accelerate the development of 3D tissue‐like constructs for regenerative medicine.