Patient holds 3-D printed skull implant. Image courtesy Materialise.
Yes, you can, indeed, print a working gun, as young American Cody Wilson demonstrated earlier this year, garnering headlines in the process. You can also use 3-D printing technology to make things that will improve the human condition, and many in the medical device space are doing just that.
Printing body parts and organs has captured the public imagination, and companies such as Organovo and TeVido BioDevices are heavily invested in that pursuit. But it will be some time— a lifetime, say some—until that research fully comes to fruition. The fact is, 3-D printing has already revolutionised medical technology, from prosthetics that provide a better fit yet cost less than traditionally manufactured implants to patient-specific guides that take the guesswork out of surgical procedures. These advances are not as glamorous as on-demand organs, and consequently are not capturing headlines, but they are significantly changing our lives for the better today.
Bioprinting market growth
The overall market for 3-D printing grew 28.6% in 2012 to US$2.2 billion compared with US$1.714 billion in 2011, according to Wohlers Associates Inc., which publishes annual reports on the global additive manufacturing and 3-D printing markets. Continued double-digit growth is forecast for the next few years, and the sector will hit US$8.4 billion by 2025, according to Lux Research. The bioprinting subsector will account for approximately US$1.9 billion of the total; most of that will come from printed medical devices and orthopaedic parts.
3-D Printing Live
3-D Printing 101 will be presented by Stratasys at the Tech Theater, a new addition to MD&M Chicago, held at McCormick Place Lakeside in Chicago on 10 to 12 September.
“In orthopaedics, 3-D printing is already having a huge impact,” says Eric Bredin, Marketing Director Europe, Stratasys (Rheinmünster, Germany). “More than 40,000 hip socket replacements have been made using 3-D printing. By improving the patient’s quality of life through better fitting prosthetics, while reducing cost, 3-D printing is pushing the envelope in terms of personalised prosthetics,” he adds.
Christian Wielk couldn’t agree more, although he is coming at the technology from a metals perspective. “I expect direct metal laser sintering to become the industry standard in the production of metal implants,” says Wielk, Managing Director, Medical Division, at MediMet Precision Casting and Implants Technology (Stade Wiepenkathen, Germany). “Small or complex implants will benefit,” he adds. Wielk expects production costs to decrease as throughput rises and raw material prices decline. MediMet Precision is part of the Alphaform Group, which will exhibit at World Medtech Forum in Lucerne, Switzerland, from 17 to 19 September.
Making surgery safer and smarter
Surgical procedures and the instruments that enable them have made considerable strides thanks to 3-D printing. Belgian company Materialise (Leuven) has been very successful with its patient-specific guides, also called patient-matched cutting blocks. Based on a patient’s CT scan, the printed device sits on the surgical site and indicates where and at what angle to drill. “No more eyeballing,” says Business Unit Director Koen Engelborghs. “We print thousands of these per month, some of them for large orthopaedics companies.”
Direct metal laser sintering will become the industry standard for the production of metal implants—Christian Wielk, MediMet Precision Casting and Implants Technology.
Materialise, in collaboration with daughter company OBL, also produces custom implants, and achieved a breakthrough of sorts printing a perfectly fitted skull implant. “It has a porous structure that promotes bone ingrowth and vascularisation,” says Engelborghs. He adds that 3-D printing is the only way to achieve this combination of properties.
The availability of flexible materials for 3-D printing has advanced the optimisation of medical instrument design, according to Engelborghs. “Animal testing at some point refines device design so that it is better suited to animals than humans,” he says. The use of 3-D anatomical models produced by additive manufacturing techniques with flexible materials that mimic the properties of human artery walls are a better alternative. The company’s HeartPrint Flex is a proprietary process that combines flexible and rigid materials in a model that is suited for visualising catheter movement, R&D device deployment or fluid flow.
“It’s not uncommon to read articles about how 3-D printing technology will enable us to print a heart or leg in the next five to 10 years,” says Engelborghs. “That is not realistic. The human anatomy is amazingly complex,” he adds, and not easily digitised. (That’s not stopping Organovo, which has teamed up with Autodesk to develop CAD programs that could be applied to bioprinting.) But you will increasingly see 3-D printed small body parts and small organs within the next five to 10 years, says Engelborgh. He cites the inspiring story of a newborn who, in all likelihood, is alive today because of a printed bioresorbable splint.
The baby was born with a collapsed bronchus that blocked the flow of air to his lungs. The splint was sewn around the child’s airway to expand the bronchus and provide a scaffold to aid proper growth. Once it has done its job, the splint will be resorbed by the body. Software developed by Materialise contributed to the creation of the splint. It’s an understandable point of pride for Engelborghs and the Materialise team.
— Norbert Sparrow