As is now well known, the world of 3D printing is proposing solutions that were previously unattainable for those in need of a prosthesis. With a few dollars we can now produce a prosthetic hands in PLA or ABS. However a welcome innovation now arrives from the specific area of silicone prosthetics and the covers that can reproduce our limbs realistically.
Erica has been working on it for just two years, experimenting with custom silicone prosthetics obtained through 3D printing. Thanks to her commitment, her ability and collaboration not only from WASP but from a full research team, her work has already raised the interest of both amputees and enterprises providing prostheses in developing countries and in America.
Erica Buzzi is a sculptor and a silicone implants design engineer. For several years she has worked with orthopedic technicians, experimenting on how to apply the most advanced technologies. She is currently a consultant for the construction of aesthetic orthopedic centers for several Italian laboratories working in the field..
In 2013, fascinated by the possibilities offered by 3D printing, she decides to stop by the WASP headquarters and the empathy was immediate. “I almost did not believe it – she says – all it took was a conversation with Massimo Moretti, I explained my ideas, my plans, my dreams. And he immediately made his machines and his team available.”
Soon thereafter the print and tests and verification process began for several solutions. “Starting from the scan and its post processing to improve the details, the process moved on to the g-code file generation – explains WASP’s Nicola Schiavarelli – The vertical positioning of the stamp was important to enable the highest definition of the mold. Apart from this aspect, it was crucial to speed up the printing process, so the piece was 3D printed totally empty. It would be possible to make it more robust by filling it with polyurethane foam, but it was not necessary for the first tests. In factthe first mold for the silicone prosthesis was built in 8 hours using fused filament additive technology.
3D scanning – Nicola continues – is definitely very important factor. At this stage the acquisition of details is the most difficult part but it is also that which will ensure the best results. It also became clear that the layers created by 3D printing made it easier to obtain the skin-effect finish on the silicone”.
“With FabLab Parma and Pocaterra Srl in Bologna we tested scanners and modeling software, while with “Con le Ali Piedi”, also from Bologna, we applied technologies on the silicon to actually fabricate the covers” adds Erica Buzzi.
Low cost, high quality, customized implants. These are Erica’s research objectives and she can now legitimately claim to have concluded this trial with excellent results. “But we never stopped because in these very days we are developing a solution to provide integrated silicone prosthesis with ultra-light joints for children without arms. And the will be affordable specifically because they need to change through a lot of them as they grow”.
3D printing enabled a reduction of the time necessary for the various stages of production. “Through the 3D scanning management software, a missing foot can be designed using the remaining one – we read on the www.protesiinsilicone.it website – so as to maintain the accuracy of shapes and details. With the 3D modeling, in the pre-print stage, the necessary molds for the construction of the prosthesis are built, along with those for the silicone cover. The free-hand, wax reconstruction phase is thus eliminated, as well as those involving casting resins and gypsum mold manufacturing. This beings considerable savings in time, material processing, laboratory equipment and highly specialized labor in certain phases of work. ”
For printing, Erica uses a DeltaWASP 2040 with 0.1 mm definition. “It gives a good feedback. And allows both to contain costs and obtain a very precise and qualitative final product “.
Built in PLA (a material that does not interfere or contaminate the silicone hardening process), the empty mold is then filled with plaster. Part of silicone processing is done by hand. A curiosity: during certain stages of the process, such as sample preparation of colored silicone for the nails, or each patient’s color chart, even a simple and economical pasta-making machine can be used.
“With support form funds and facilities – Erica concludes – testing will be increasingly developed and refined in order to achieve further advances in technology and performance.”
The silicone implant prostheses made with current procedures are very expensive and thus beyond the reach of most people. The national health system does not cover them, or covers them only minimally, compared to market prices. Producing them with a better technology, at much lower costs cost is Erica Buzzi’s dream. That’s why we now consider her a perfect WASPer.
