Injuries and degenerative conditions of the musculoskeletal system — sports-related tendon or ligament ruptures, damage to articular and osteochondral cartilage, and age-related osteoarthritis — are a common and pressing problem in all modern societies, and particularly in Europe given its ageing population. Because such injuries are painful and heal poorly, they frequently require surgical treatment. Since natural healing processes and the reconstruction techniques currently available in the clinic (for example, bridging tendon defects with sutures) are not very effective, researchers are looking for alternatives, and tissue engineering has emerged in recent years as a promising approach. The discipline aims to produce constructs in the laboratory that can mimic complex native tissues in both structure and function. In this context, 3D printing technologies offer promising opportunities to fabricate new biodegradable scaffolds and tissue constructs, tailored to specific tissues and patients, which after implantation will support the complete regeneration of defects in the body.
This project, carried out in international collaboration, therefore aims to create new types of implants and tissue constructs that support the full regeneration of the common defects described above, which occur at the interface between different musculoskeletal tissues. We will focus in particular on two tissue types (see Fig. 1): the bone–cartilage and the bone–tendon junction. In our research we will use 3D printing to produce these complex tissues.
A full set of studies will be carried out to achieve this goal. First, we will propose new scaffold printing patterns designed to better support the growth of cells seeded in the scaffolds and to give the scaffolds structural and mechanical properties similar to native tissue. The proposed architectures will be alternatives to those currently in common use in 3D printing. Second, we will identify — or develop new ones as needed — suitable biomaterials for printing these patterns. Finally, we will combine different state-of-the-art printing technologies to obtain complete, complex tissue mimics. We will also use computational modelling to predict the mechanical properties of the printed scaffolds.
The proposed approach will allow hierarchically organised constructs to be fabricated and can readily be applied to producing mimics of other complex tissues of the human body. The project has considerable social relevance and addresses currently unmet clinical needs for functional implants and in vitro tissue models representing complex tissue junctions. Our research will also benefit other scientific disciplines by providing new printing patterns and computational models for predicting the properties of such printed constructs.
