Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - FAST (Functionally graded Additive Manufacturing scaffolds by hybrid manufacturing)

Teaser

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, up to the’50ies and ’60ies of the last century, prostheses have been the solution. New materials such polymers...

Summary

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, up to the’50ies and ’60ies of the last century, prostheses have been the solution. New materials such 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 even a 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 late ‘90ies, biological research advances on one side and material developments have allowed to think even further. The goal of the developments shifted from tissue replacement to tissue regeneration. In the future, we will have an uncle with 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 the 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 is aiming 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 3D printing flexibility, melt compounding adds the possibility to print 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 in order to obtain the desired tissue growth.
Atmospheric plasma treatment or deposition during the 3D printing process allows the surface chemical functionalization further controlling cells growth and differentiation.
These technological advances will allow a cost reduction, the possibility to make the scaffolds easily available and affordable and improve patient lifestyle also by reduction recovery duration.

Work performed

The project has started with the development of the novel HAM technology in all its aspects in parallel: the new composites materials, the novel atmospheric plasma processes and the HAM devices design and prototyping. All these developments are planned to conclude within the first 18 months of the project in order to leave enough time in the rest of the project to test their integration, pilot production testing of scaffolds and evaluation up to preclinical tests.
At this stage, it has been achieved:
• production of lamellar fillers based on hydrotalcites with smart functionalities such as antibiotics
• production of reduced-GO (r-GO) with different densities
• production of masterbatches with both fillers by twin-screw extrusion and dispersion up to 40w% of hydroxyapatite by solvent blending
• deposition of amine and epoxy functionalities at room temperature. Novel requirements to improve the prototype that is under development have been addressed.
• design and prototype manufacturing of the printing head that mixes the masterbatches while printing
• a second system with cartridge/piston to reduce equipment costs
• design and prototype manufacturing of the novel atmospheric plasma jet to be installed in the printing platform.
All these development are carried on keeping in mind ethics and safety rules not only for the research and development itself, but also for the future manufacturing and exploitation on larger scale. In order to help the observance of the nanosafety requirements, the project became part of the “Industrial Innovation Liaison (i2L)”.
Meanwhile, the first presentation of the project in scientific conferences and fairs has started with the aim of improving the awareness of the project in the different communities and at the same time to test the interest of customers and of the market.

Final results

The FAST project aims to develop and offer to the market a novel Hybrid Additive Manufacturing (HAM) device for producing scaffolds for tissue regeneration. The HAM device and materials developed in the project are focused in bone regeneration applications.
Orthopedic implants is a worldwide growing market even in emerging countries. A common fact that determines this growth worldwide is the population ageing. The UN projects that by 2050, over 400 million, or nearly 33%, of Chinese citizens are expected to be over 60 years old, a number that is greater than the estimated entire population of the United States in 2009. This is due to the increase of the welfare and of the life expectancy. To these ageing problems, also the increase of lifestyle introduces other causes for orthopedic implants such traumas due to car accidents that follow the increase of automobile ownership. The implementation of HAM technologies enables the localized production of the scaffolds by synthetic materials making them therefore easily available in the needed quantity also in less technological advanced areas. This feature will have a strong social impact in satisfying the increasing demand of scaffolds. Moreover, HAM produces scaffolds better than the existing ones, allowing to adapt the scaffolds to the individual patient and improving the implant quality by reducing healing time and enhance tissue regeneration, which means less problems after implanting. Furthermore, the bio-active features will allow a reduction of the infections due to surgery. Moreover there will be no more need of donors that often present long waiting lists. Therefore, the uptake of the HAM technology will lead to a better quality of life for each individual patient and these benefits will make a positive social impact.
At the moment, no AM device is present on the market that includes the hybrid features proposed in the FAST project.

Website & more info

More info: http://project-fast.eu/en/home.