People have always had to face the need of repairing parts of the body, mainly limbs and teeth, in the aftermath of ageing, injuries or diseases. For centuries prostheses have been the solution. New materials such as polymers, composites, and electronics have allowed a strong improvement in the performances of these devices, from hearing aids to the carbon fibre foot for runners. Such developments are improving the daily life of many people allowing a better lifestyle.
However, the development of materials has allowed an even deeper advance for human health: the possibility of implanting parts of the body spanning from bones such as femur, up to cardiac valves or stents. “Biocompatibility” has been the master rule for the development of implantable materials and devices for decades. The results of these researches are now common tools for healthcare, such as dental implants.
From the late ‘90ies, biological research advances on one side and material developments on the other side have allowed to think even further. The goal of the developments shifted from tissue replacement to tissue regeneration. In the future, we will not have an implanted metallic ankle, but a new regrown bone.
Our body has an innate capacity to regenerate itself. However, when critical size defects are presented (e.g. typically in the range of at least one cubic centimetre), tissue regeneration strategies are needed. Tissue regeneration is a complex topic that requires a multidisciplinary approach, from (stem) cell biology and cell growth to the interface interactions between materials and cells. From a technological point of view, “scaffolds”, i.e. temporary porous structures housing cells, and “bio-degradable” materials are the new master rules for the development of tissue regeneration constructs. The challenge to address when fabricating scaffolds lies in the fact that the organization of tissues and organs in the human body is difficult to replicate. Scaffolds need open and completely interconnected pores with dimensions typical in the order of hundreds of microns but also nano-scale morphology, surface chemistry but also mechanical properties to guide the desired cell activity and tissue formation.
The FAST project aims to offer a novel production device able to obtain in a single production process all these requirements, hybridising the Additive Manufacturing (AM) technology with melt compounding and atmospheric plasma.
To AM flexibility, melt compounding adds the possibility to deposit not only polymers, but also polymer nano-composites with high content of nanofillers improving mechanical properties, allowing smart functionalities (antibiotic release, …) or guiding stem cell differentiation to obtain the desired tissue growth.
Atmospheric plasma treatment or deposition during AM allows surface chemical functionalization, further controlling cell adhesion and proliferation.
These technological advances allow a cost reduction, the possibility to make scaffolds affordably available and may hold the potential to improve patient lifestyle by reducing the recovery duration.
