“Esoteric euphoria.” That’s what our Additive Manufacturing team felt when watching Team GB in the Men’s Hockey at the Tokyo 2020 Olympics. Obviously, we were saddened by our trouncing from India in the Quarter Finals, but, the fact of the matter is, *that* mask worn by Samuel Ward… we made that.

More specifically, we 3D printed the custom Raptor Mask on behalf of 3D Ortho Pro on our HP Multi Jet Fusion 5200. The PA 11 Nylon print then underwent a finishing process of surface polishing and dyeing before assembly.

The Raptor Mask, a bespoke protection device made specifically to fit the contours of Sam Ward’s face, is an example of the rapidly emerging trend in personalised orthoses, prostheses and body armour produced through polymer additive manufacturing, or 3D Printing.

Customisation evolution

Aside from the obvious, recent scale up in vaccine development, very little over the last two years has driven a market trend in the medical and healthcare sector as fast as the advent of utilising additive manufacturing methods for creating custom orthoses and prostheses.

Traditional methods of fabrication, including casting and moulding, are labour intensive, time consuming, and often involve copious amounts of material waste. Now, we can print orthotics from insoles to skull caps that exactly fit an individual’s anthropometrics in a few hours. Using some technical wizardry that converts a precise scan of the individual’s foot (or head) to a CAD file, labour intensity is also removed from the equation.

In 2019, the medical and healthcare industry was deliberating whether additive manufacturing was going to be ‘a good thing’. The two main concerns were, a) the lack of ‘integrated technologies with additive manufacturing procedure’, and b) would the resultant product really meet functional requirements and yet provide comfort to the wearer?

The ‘integrated technologies’ issue has been resolved. Invent Medical, for example, has created a 3D printing digital platform, with the aim of ‘democratising’ 3D printing for healthcare specialists. The configuration software is free. The system amalgamates AI, machine learning, anatomical data and algorithms, shortening design time of a custom orthosis to minutes and driving costs down.

And, as for comfort and functionality? When something is a perfect fit, much of the comfort factor and some of the functionality is taken care of. The remainder pretty much comes down to design and materials.

Design freedom and mass customisation

Polymer additive manufacturing offers some unique advantages over traditional orthotic and prosthetic creation methods. For example, it’s a relatively simple process to integrate complex lattices and material voids within the orthosis. Where voids enable ‘lightweighting’; lattice structures complement in at least two ways – they strengthen the structure; and deliver on customised cushioning and impact protection.

Thus, when it comes to design, structural complexity isn’t a limiting factor. The beauty of additive manufacturing is that material is only added where it needs to go. Complexity won’t impact production costs significantly. Costs may actually come down due to lower material consumption. This, in turn, gives you the opportunity to optimise your designs during development without having to modify moulds or create new tools, or incur the costs every time you make a slight adjustment.

Image by kind permission of Ortho 3D Pro

Image by kind permission of Invent Medical

Print Production

Until recently, additive manufacturing of orthotics and prosthetics involved the following processes:

  • Fused Deposition Modelling (FDM or, occasionally, FFF), is a thermal extrusion process offering a low-cost material solution. However, the materials are often rigid, surface quality straight off the printer requires work, print time is lengthy (up to 14 hours for an insole, for example)
  • Stereolithography (SL) and Digital Light Processing (DLP) are photopolymerisation processes. They offer improvements on surface quality but require support structures (and that means a lot of post-processing to factor into the creation time), and materials are relatively expensive
  • Selective laser sintering (SLS) involves the fusion of powdered polymer-based materials with carbon dioxide. Using nylon produces a great result, but drawbacks are that there’s a great deal of post-processing required and the end result is stiff and porous.

In 2016, print technology giant HP introduced a new player into the AM arena. Multi Jet Fusion (MJF) has  significant recyclability value, is quick and extremely precise, the surface finish is superior, and is sizeable enough for mass customisation. With an open materials platform and an automated post-processing facility included helping to drive costs down further, MJF was immediately recognised as the panacea to the healthcare additive manufacturing conundrum.

We took our own investment in the HP Jet Fusion 5200 and 4200 printers a step further, augmenting the capability with a post processing suite from DyeMansion. This enables us to deliver parts with an even smoother finish and allows our customers to choose from some 170 RAL, biocompatible colours.


What of other polymer AM technologies, such as Carbon® Digital Light Synthesis™? Offering layer-less, highly accurate, isotropic parts in an array of engineering grade resins from rigid polyurethanes to flexible silicones, it seems that this could offer a competitive alternative to the MJF process. The technology is designed to deliver on complexity and speed; its only real drawbacks being that currently, the print bed is quite small and colouring parts could lead to a loss in integrity. The benefits probably supersede those of MJF prints when it comes to small, robust parts incorporated into prostheses, such as mechanical housing, joint components, buttons, connectors and cosmeses. With over 12 production resins to choose from, Digital Light Synthesis technology comes into its own when it comes to lattice production for personalised cushioning and impact protection for body armour.


When selecting materials for any printing project, the physical properties such as robustness, durability, strength and heat resistance are priorities. In the instance of orthoses. prostheses and body armour, wear resistance and density are also top considerations.

PA 11 Nylon has most of the attributes required for orthoses and prostheses. It’s light weight, slightly flexible, moves with the patient, and strong. It can take mechanical loading and it’s also ductile, which means lattice structures aren’t an issue. As a bioplastic, it is produced from renewable plant sources, checking the sustainability boxes straight away. It’s biocompatible, grease and chemical resistant, and it’s also water resistant, with increased dimensional stability when exposed to moisture. Swimming with a 3D printed wrist splint is absolutely doable.


In conclusion, the Multi Jet Fusion process, utilising PA 11 Nylon, is currently the ultimate additive manufacturing solution for orthotics and prosthetics. The industry moves fast, though, and who knows what might disrupt the industry next year or the year after?

In the meantime, the technology and material lead the way to produce personalised orthotic insoles, cranial remoulding orthoses, paediatric and adult AFO, body armour for sports and myriad prosthetic components. Companies such as Invent Medical, Technology in Motion and Ortho 3D Pro have embraced the innovation with open arms to create the next generation of mass customisation orthotics and prosthetics.

For more information, please contact Becky Eskandari or call 01325 333 141

Image by kind permission of Invent Medical