LayerWise made headlines this month when it unveiled the world’s first custom-made total lower jaw implant, "printed" from a 3D schematic.
The device was constructed layer by layer from a digital file mapped to the patient’s jaw, a process called "metal additive manufacturing" that Belgium-based LayerWise has used in making custom spinal implants, cranial plates and acetabular implants.
"The great advantage is that it is a technology capable of realizing the most complex geometries," Mercelis told MassDevice. "This makes it possible to build components with increased functionality that would otherwise be impossible to manufacture or at least would be very expensive with other technologies."
Called "additive manufacturing," the printer layers thousands of thin sheets of metal based on a 3-dimensional computer-aided designed mapped to a patient’s physiology.
In an exclusive Q&A with MassDevice, Mercelis told us about the path to building the world’s first custom-made total jaw replacement, the lessons learned and the growing potential of 3D printing for custom medical devices to disrupt custom medical implant manufacturing.
MassDevice: In brief, how did LayerWise come to be?
Peter Mercelis: LayerWise was established in 2008 as a spin-off company of the University of Leuven in Belgium. LayerWise was founded by Peter Mercelis and Jonas Van Vaerenbergh, who both hold a PhD degree in metal additive manufacturing. LayerWise focuses on metal additive manufacturing technology and targets industrial, dental and medical sectors.
I am one of the founders of LayerWise and CEO of the company. I mainly occupy myself with the dental and medical applications, while my co-founder Jonas Van Vaerenbergh mainly deals with the industrial applications.
MassDevice: Tell me about the process of implanting the first patient-specific lower jaw. Was LayerWise looking for an opportunity to test a medical device? Why did you choose a lower jaw?
PM: LayerWise was not looking for an opportunity. It was the surgeon that contacted us, since he was confronted with a patient with a very severe osteomyelitis, that could not be treated any other way. The surgeon knew our company from previous joint research projects and was aware of the possibilities of metal AM technology.
Initiated by Prof. Jules Poukens, of the University of Hasselt, Belgium, LayerWise printed the implants using its additive manufacturing technology, based on a 3D design performed by medical design company Xilloc Medial BV of the Netherlands.
MassDevice: What was the regulatory pathway?
PM: The device concerned is a custom implant. Therefore, it was prescribed by the surgeon. It was manufactured from ISO-certified materials under our company’s quality management system according to ISO 13485 guidelines. A technical file was prepared for the specific implant.
MassDevice: What were some of the challenges in producing the implant?
PM: The implant required not only 3D printing process using selective laser melting technology, but also some additional operations; polishing of the articulating surfaces, provision of threaded holed for dental implants, a hydroxi-apatite coating, etc. Coordination of all the operations and technologies involved was quite a challenge.
MassDevice: What were the takeaway lessons?
PM: It is very important to have a good coordination among different project partners involved. We learned that a good case preparation requires a lot of time, but is essential. The operation went so smoothly, because of the intense and punctual preparation of the case.
MassDevice: What was the inspiration for LayerWise’s medical device operations?
PM: During the technology development stage at the University of Leuven (both my colleague Jonas van Vaerenbergh and I did PhD research on Selective Laser Melting technology), medical implant manufacturing was one of the first and most logic applications of the metal AM technology.
Discussions with surgeons indicated a clear need for patient-specific implants, but also the potential of metal AM for serial manufacturing of medical devices was clear, thanks to the high shape-complexity of some medical implant devices and the possibility of building biocompatible materials with AM. From the start-up of LayerWise in 2008, we intensively worked on the optimization of the metal AM technology for medical applications.
MassDevice: This seems like a potentially disruptive technology for medical device manufacturing. Is it?
PM: That is definitely the way we see it.
MassDevice: In very simple terms, how does the process work?
PM: The process starts from a 3-dimensional CAD model of a component. The component is then virtually sliced by software into a set of 2-dimensional layers. Next, the first layer of the 3D component is built by using a focused laser beam that is scanned over a powder bed. The focused laser beam melts the metal powder (e.g. a titanium powder) and when the molten layer solidifies again, the first layer of the component is created. Next, a fresh thin layer of powder is spread over the build area, and the second layer of the component is scanned with the laser and fused on top of the first layer. This process continues on and on until the complete 3D object is created. A typical object consists of a few thousands of thin layers that are molten together. Due to this layer-wise build strategy, very complex geometries (complex surfaces, integrated porous structures, etc.) can be manufactured.
MassDevice: How does metal AM compare to traditional manufacturing?
PM: Metal AM is not a replacement technology for any existing technology, but it does bring new possibilities for manufacturing complex components. If you compare the build rate of the metal AM technology, this is low compared to the removal rate of CNC machining. It is therefore a rather slow and expensive technology. The great advantage is that it is a technology capable of realizing the most complex geometries; this makes it possible to build components with increased functionality (that would otherwise be impossible to manufacture or at least would be very expensive with other technologies). It is important to know that metal AM technology is perfectly compatible with existing manufacturing technologies (wire EDM, milling, turning, grinding, etc.).
MassDevice: What need is LayerWise looking to fill in the medical device manufacturing arena?
PM: We believe that additive manufacturing will not only be a possible new manufacturing technology to produce medical implants, but due to the nature of the technology, it will also offer new possibilities to increase the functionality of medical devices, since geometric shapes and structures can be built with AM technology, which were not possible up to now.
MassDevice: What types of devices are good candidates for metal additive manufacturing?
PM: Since AM technology is very well suited to manufacturing complex geometries, many medical implants make good candidates for AM technology. Of course, custom patient-specific implants are good candidates for AM, since traditional manufacturing techniques are not well suited to manufacturing custom implants. On the other hand, applications are not limited to custom implants, and also serial manufacturing with AM technology is perfectly possible. Examples of good candidates are spinal implants and components, cranial and maxillofacial implants, small joint prostheses (finger, elbow, toe, shoulder, etc.), hip cups and stems, etc.
MassDevice: What types of devices are not good candidates?
PM: Since AM technology is generally a rather slow technology in terms of production rate (cubic centimeters build rate per hour), and rather expensive (manufacturing cost per hour) voluminous components with rather simple geometries are not good candidates for AM technology. In both cases, cheaper methods exist (casting, forging, etc.) to manufacture the device. Large instruments, voluminous knee joints, etc., may be too expensive to manufacture with AM technology in comparison to other manufacturing techniques.
MassDevice: Your website mentions that LayerWise has garnered interest from industries such as dentistry, orthopaedics, maxillofacial and spinal surgery. What other devices have been created and implanted in patients so far?
PM: Many custom dental prostheses have been manufactured with our AM technology. This is done through our separate division DentWise. Examples of other medical devices that we have manufactured up to now are custom CMF implants (orbital reconstruction, sinus reconstruction, custom cranial plates, etc.); custom acetabular implants (these are commercialized and designed by the company Mobelife NV in Belgium); spinal implants; and trauma fixation plates.
MassDevice: What’s next for LayerWise’s medical device operation?
PM: LayerWise will continue to develop and optimize its Additive Manufacturing technology, facilitating the use of metal AM for implant manufacturing. Mass production of medical devices with AM technology is already possible today for certain types of implants and the range of medical devices that can benefit from AM technology will grow parallel to the technical evolution of the manufacturing technology.
MassDevice: What’s the long-term plan with this technology? Do you plan to bring it to the U.S.?
PM: LayerWise is able to work for U.S. customers already. LayerWise operates under a quality management systems certified according to ISO 13485 guidelines. Of course, depending on the customer’s application or product, a dedicated certification involving FDA clearance/approval will be necessary to enter the U.S. market, but this should not form a barrier for entrance in the U.S.