Additive manufacturing technology has opened up possibilities for the production of medical products that can change the way reconstructive medicine is done all over the world.
It was the stuff of science fiction and comic book superheroes. That is, until a senior patient received the world’s first custom-made, 3D printed, titanium full jaw implant in a surgical operation that restored the patient’s facial aesthetics and allowed her to regain her speech in a matter of hours. With the success of the replacement/reconstructive surgery, the technology that produced this premier patientspecific metal mandible could very well be the shape of things to come.
Created layer by layer using the technology more popularly known as 3D printing, the titanium jaw implant was not only highly personalized but highly biocompatible as well. ‘Such implants have excellent form and function; they speed up surgery and patient recovery, and reduce the risk of medical complications,’ KU Leuven Research & Development (LRD) states in an impact report it prepared about the technology. Post-processed with ceramic coating, the titanium jaw also integrated multiple functions, and true to form, restored the elderly patient’s facial aesthetics, allowing her to regain her speech within hours, the report adds.
As the four-hour reconstructive surgery was undoubtedly painstaking, LayerWise, one of the companies behind the operation, also took great pains in bringing to life the type of technology that made the metal implant conceivable. The company manufactures revolutionary orthopedic, maxillofacial and dental implants, as overseen by its medical and dental divisions. It also has an active industrial division with applications not only in the biomedical field but also in aerospace, marine, and several other industries.
Founded as a spin-off company from the Department of Mechanical Engineering at the Belgian university KU Leuven, LayerWise, is the first of its kind in Belgium to exclusively focus on metal additive manufacturing (AM) or ‘the industrial version of 3-D printing,’ as MIT Technology Review calls it.
Revolutionary manufacturing
MIT Technology Review explains: additive manufacturing (AM) is ‘additive’ for the simple reason that ‘it builds an object by adding ultra-thin layers of material one by one.’ Fully computer-aided, additive manufacturing uses high-power lasers to rapidly melt industrial materials, such as polymers, metals, composites, and biomaterials, and just as easily spread, dry, and fuse together one ultra-thin layer of material onto the next. The meticulous layering is repeated until the desired object is created.
LayerWise co-founder Jonas Van Vaerenbergh takes pride in the fact that the company’s technology is additive rather than subtractive. He explains how their core business is ‘to build up material in layers instead of removing it in different steps.’
Because the AM approach is capable of simultaneously producing functional metal parts of different shapes in series of up to 50000 pieces, the high-speed production allows LayerWise to drive down production costs for its clients, Van Vaerenbergh says. On top of production efficiency and cost-effectiveness, AM is hardly constrained by the geometry of an object that needs to be produced. LRD General Manager Paul Van Dun calls additive manufacturing ‘a disruptive technology.’
Professor Jean-Pierre Kruth, a member of the Faculty of Engineering Science at KU Leuven and now promoter of LayerWise, agrees with Van Dun, saying the biggest impact of the AM technology is
that it is a real ‘revolution in manufacturing.’
Citing the medical applications of AM, Kruth explains that because no two persons are alike, many of the implants have to be made dedicated to the person. He says AM offers ‘the freedom to make components that are totally customized, especially those that are so complex in geometry that they cannot be made by other manufacturing techniques.’ Kruth says titanium is preferred and used as an AM material in dental and medical applications because because it is biocompatible and allows to make implants lighter. He explains that titanium, typically used in the manufacture of aircraft, spacecraft and other vehicles, is also favored for its palliative, nonaggravating effects.
3D designs
Today, LayerWise is one of the latest and most important acquisitions of the US technology giant, 3D Systems (3DS). Acquired by the 3D digital designs and fabrications company in 2014, LayerWise has no doubt seamlessly added a new dimension to the portfolio of 3DS. That the Belgian company has become part of the US company is only fitting as it was rapid prototyping, developed by 3DS in the 1980s, that laid the very foundation for LayerWise’s AM technology. Kruth still remembers how this groundbreaking technology first made its way to the Belgian academic community. ‘The very first machines from 3D Systems were demonstrated in 1988, and the very first installations of the machines occurred in 1990,’ the professor recounts. ‘We at the University of Leuven were among the first to acquire that kind of machine called the stereolithography machine. And that’s where it all started.
LayerWise CEO Dr. Peter Mercelis (left) with Professor Jean-Pierre Kruth (right).
Indeed, 3DS paved the way for LayerWise’s AM technology with the US company’s invention of the stereolithography apparatus (SLA), first commercialized in 1989. Coined by its inventor and patentor Charles W. Hull, stereolithography involves the three-dimensional ‘printing’ of liquid plastic. That is, an SLA instantaneously draws out, spreads, and hardens ultra-thin layers of liquid photopolymer using ultraviolet (UV) rays.
The UV-curable liquid is also drawn out and laid to dry one layer at a time until a three-dimensional image is created, giving rise to 3D printing as we know it. Having invented the machine a few years prior, Hull successfully went on to found 3D Systems Inc. in 1986. LayerWise’s AM technology is, in fact, a type of 3D printing, the latter originally developed under the name ‘rapid prototyping’ because, despite being a quick process, it was mainly feasible to produce plastic objects and components that could not be tapped as real functional products, and were mainly used as visual prototypes. Who would have known that from printing plastic 3D models of objects, rapid prototyping would evolve into AM technology using metals such as titanium to make the world’s first functioning mandibular implant?
Layer by layer
Unlike rapid prototyping, the establishment of LayerWise was anything but instantaneous, although it did seem to have mimicked the layer-bylayer process of 3D-imaging. Kruth, who has been
involved in manufacturing engineering for many years, chronicles the technological developments that led to the spin-off company’s establishment, especially as they coincide with his own career. In fact, for nearly three decades, the professor needed to acquire expertise in the trifecta of technological advancements that preceded AM, and by extension, LayerWise: non-conventional machining, computer-aided design systems, and plastic injection molding.
Kruth refers to these processes as the ‘three drives’ that pushed him to look into additive manufacturing. AM, he says, is a kind of non-conventional machining because it has had to use an uncommon method, as opposed to milling, boring, grinding, and similar traditional metal-cutting processes. AM mainly uses lasers and therefore qualifies as non-conventional or non-traditional machining.
Added to the laser technology that makes AM possible is computer-aided design (CAD) on which, Kruth says, AM is predicated from the time of CAD’s development in the 1980s. ‘Before that,
you could not think of additive manufacturing,’ he says. Completing the trio of technology that shaped AM is plastic injection molding, the technology that antedated 3D’s stereolithography for the production of plastic objects. LayerWise founders Jonas Van Vaerenbergh and Peter Mercelis were both completing their doctoral thesis on Selective Laser Melting, a type of additive manufacturing that allows one to create solid objects from metal powders, when they first realized the potential industrial applications of the technology.
Mentored by Kruth at KU Leuven, Van Vaerenbergh and Mercelis sought and received seed funding from LRD, KU Leuven’s technology transfer office, and went on to found LayerWise in 2008.
Dr. Peter Mercelis (left) and Dr. Jonas VanVaerenbergh (right) founded LayerWise in 2008.
Van Dun describes the technology transfer of the metal AM technology from the university to a company as ‘fortunate from both sides.’ As a technology transfer office (TTO), LRD is fortunate
to be working with Kruth and his students because the professor has prior experience, having created two other university spin-off companies before LayerWise, says Van Dun. As for LayerWise, the existence of LRD since 1972 means they can tap into a solid experience in setting-up and growing high-tech companies. ‘Setting up a company is always about team work,’ Van Dun says. ‘If that is not possible, forget it.’