With this application, the part was split up automatically into 2D layers, and those cross sections were sent to the 3D printer, where a laser beam melted successive thin layers of titanium powder, which fused together to form the part. This process was repeated with each cross-section melted to the previous layer, and it took 33 layers to build just 1mm of height. Once the part was 3D printed, the part was treated with a bioceramic coating to make it look and feel more like a human bone.
LayerWise believes this is just the tip of the iceberg in terms of how additive manufacturing (AM) can be applied to advanced medical implant design. "AM's freedom of shape allows the most complex freeform geometries to be produced as a single part prior to surgery," said Dr. Peter Mercelis, managing director of LayerWise, in a press release. "Patient-specific implants can potentially be applied on a much wider scale than transplantation of human bone structures and soft tissues. The use of such implants yield excellent form and function, speeds up surgery and patient recovery, and reduces the risk for medical complications."
Prosthetics seems to be the next budding market with huge potential for 3D printing .Custom designs, uniquely adaptable to any particular patient anatomy, and the ability to fabricate these custom parts literally overnight, is a futuristic 21st century reality. To take it a step further, developing bio-materials as the next-generation polymer replacements, is a fantastic direction for the industry.
From a design engineers' perspective, this is an exciting field of the "front-end" of design opportunities.But what about the "back-end" --- meaning accelerated life testing of the applied designs-?
What kind of evaluations have been performed by the industry, or by LayerWise; such as materiel integrity over time and extended use (chewing as life-cycling), and especially the physiological compatibility of the foreign material within a human body? Certainly nothing insurmountable, but also this is clearly a requirement in order to claim a 100% design solution.
You raise two good points, Jim. I would hope that lifecycle testing is part of the early-stage evaluation of both the materials and the design on this jaw prosthesis as well as any other 3D printed custom implant. I know there was an added step in the printing process to make the material more "human-like" in terms of look and feel, but I don't know that it necessarily had anything to do with extended use testing. On the other hand, doctors have been using foreign materials as implants in patients for years, particularly on the orthopedics side. I would imagine the same testing/prove out process that exists there is applied to these new 3D printing material advances.
@JimT: Beth has a good point that foreign materials have been used in prosthetics for a long time.Specifically, titanium screws in joints seem to be quite common.I would not expect that each and every specific design would need to tested.Also, life testing in prosthetic replacements shows that many of them are not permanent.Artificial hips and knees will not last forever.I sometimes hear numbers like ten to fifteen years.In this case the patient is 83 years old.I expect that life testing is not a big issue.
Thanks, Beth, for covering this. Implanting devices has been going on for nearly 50 years. FDA regulations regarding biocompatible materials, including implantable ones (vs those used on the skin's surface), are at least in part modifications of ISO standards, such as ISO 10993, "Biological Evaluation of Medical Devices," which is divided into 20 different parts. The handiest brief list of 10993's 20 different parts and what they govern seems to be at Wikipedia, not at ISO or FDA's sites:
Anyway, the different types of implants being done are pretty broad, such as knees, hips, monitors, and various dental implants. The most common implantable materials are titanium and various polymers. I think what's so cool about this is the fact that it's being done with AM.
Cool article, Beth. Why was the jaw chosen as the beginning of this technology? Is it because there was greater need with that part of the body? Knee and hip replacements seem pretty advanced. Are there other parts of the body coming soon?
When researching this, I found several articles about the future of 3D printing to "print" human organs and body parts, using organic materials to "grow" body parts like blood vessels and other organs. Obviously, that's just in the research stage and likely still years, if not decades, away, but it still a very promising technology for advancing medical care far into the future.
@Beth. Medical advances look like they will the space program of the coming decades. I thinjk the oh-wow advances will be in health. That will put enormous pressure on state-funded medicine, and it will probably extend both quality of life and life expectancy.
Medical technology developments will be self-sustaining as well. Unlike the space program, medical developments are aimed to solve specific physical problems (produce a jaw, grow a bladder). While some of the research may be state funded, the resulting technology will move into the marketplace.
Rob: I agree with you that medical technology will be the "space program of the next decade." Patient monitoring -- thanks to new sensors and smart bandages -- will change the way medicine is practiced. The doctor's office could go the way of the house call.
Yes, I saw the home health care in action last week. I have a friend who was "admitted" to the hospital at home when a gallbladder operation resulted in a serious infection. He was monitored from home with visits from health professionals. We'll likely see more of that in coming years.
I expected to read a story about how surgeons built a prototype mandible for use in understanding the fit of the actual jaw bone. I did not expect to read that they built the ACTUAL mandible with a 3D printer. For whatever reason, I assumed that a "bone" from a 3D printer would be biologically incompatible for use in the patient's body. This is an incredible example of how far 3D printing has come.
@Chuck: It is pretty crazy that this wasn't an effort for building a prototype, but rather for the real McCoy. My understanding is that AM's ability to customize the mandible for the specific patient's fit is what make it such a compelling option for this particular application. And you're right, Chuck. It does show just how far 3D printing has come.
@Ann: Thanks for sharing those great links and resources. Definitely helpful for any one wanting to drill down more into the standards surrounding implants and materials choices.
This is a highly significant development, given the cases of necrotic jaw which have come to light, allegedly as a result of the use of Fosamax, a drug which was supposed to prevent osteoporosis but instead seems to have caused serious side effects. Thus is seems 3D printing will eventually join robotics and medical miniaturization (i.e., smaller data and diagnostic products) as new and valuable tools for doctors. My one question re 3D printed human parts are sterility and validation.
@Alex: I think your point about sterility related to 3D printed parts like this implant is not as acute given what we talked about before in that there is a long history of foreign implants used in orthopedics and other medical specialty areas. Thus, there is a process and best practices around ensuring these foreign substances are primed to live within the human body. The idea of 3D printing organs is a totally different animal, however. There, I think you raise some valid issues around challenges to come. My sense is we have a long way to go on that front.
I think it will be quite a long time before we can print organs. First we have to be able to create them by duplicating their functions, and I don't think we're very close to that, let alone 3D printing them.
I agree, Ann. While there's lot of research out there as to the potential, there are far to many unknowns and not fully evolved capabilities to make printing 3D organs a reality. Nice to know there is money and research time being devoted to this cause, however. Once we succeed, it will make some signficant changes in people's lives.
Beth, I hope you are right. maybe I read too much science fiction, but the idea of being able to not only fabricate, but 3D print replacement organs makes me pretty uneasy. OTOH, maybe it would help stop the illegal live/fresh organ trade.
In an unregulated world, you're right, Ann. It would be pretty scary. I guess my brain doesn't work that way. I was just thinking that for qualified/certified and totally above board medical institutions, it would be a welcome alternative to organ transplants or the worse alternative--patient loss.
I agree, Beth, and I'm sure they will be welcomed by legitimate users. Unfortunately, the illegal organ trade is alive and well in today's supposedly regulated world, which makes me wonder about the illegal trade that could occur in 3D printed organs.
To me it's neat to think of the ability to adjust the standard jaw bone to make it larger or smaller and then customize to the shape of the individual patients shape. Combine this with the ability to scan the patients face or features before the change and the possibilities are staggering.
It appears as though patients with nothing or very little to lose are volunteering for this kind of research. Unfortunately, there seems to be very little shortage of people in such a position that all they want is another go at a higher quality of life.
The LayerWise site has many photos of parts manufactured with the same types of technologies used to create the jaw bone. I thought the powdered-metal component might need sintering or annealing after construction in the 3-D printer, but it seems as though the laser actually fuses the metal particles and the printed part needs no additional processing. I'd like to see some photos that show the crystalline structure of the metal to see how the metal particles form a single piece.
I wondered if the LayerWise jaw included threaded holes for inserts to the patient could have implants to replace teeth. Perhaps the threading took place in a separate step.
Jon: The information from Layerwise is that they did create the 3D printed jaw with provisions to accomodate some sort of dental fixture. See text: "Furthermore, the mandible implant is equipped to directly insert dental bar and/or bridge implant suprastructures at a later stage."
I wasn't sure whether that meant they had threads in the holes or that they would tap the holes later. Inserts normally require a titanium fitting that threads into the bone, which them infiltrates into the insert and holds it fast. Then a post threads into the insert. In any case, this is amazing technology.
I personally have experience with titanium implants; just four months ago, I had three of my lowest vertebrea fused to my sacrum (L3 through S1). I now have eight screws, which thread through carriers, which are then held together with two vertical pins.
They expect the screws/hardware to loosen up over time, so at the time of surgery, they pulled bone marrow from my hip, and inject that into an organic sponge material and promote new bone growth between the vertebrea (disks removed) and along the titanium hardware. In days past, and still at some hospitals, they used to harvest full sections of bone from the patient's hip, or use cadaver bone to promote new bone growth. There were always problems with the patient's body rejecting the implanted bone, especially if it was harvested from a cadaver. This is not a surgery that I want to repeat due to bone rejection.
It was a long surgery and painful recovery, but I can't believe how much of my life I have back already! I have a long (10") vertical scar where they entered the back, but it is in a location that is normally covered. The x-rays are cool though, with the titanium glowing white relative to the soft tissue and bone.
Overall, it has been a positive, abliet expensive, experience, since I can tie my own shoes again. Only three days/two nights in the hospital. The only drawback so far is the extra waiting to get through security at the airport:( Thank goodness for body scanners!
Nice article. My daughter is missing two teeth (never had baby or permanent) and we have been looking at some new technology can would/could allow her grow replacement teeth. That research has been to be somewhat slow maybe this will be a good option.
@gsmith120: There does seem to be a lot of activity around 3D printing and dental applications. Check out EOS, a manufacturing of laser sintering platforms. I believe they do a lot of work in the dental segment. Perhaps they have partners using their platforms to create something that could help your daughter.
That would be really great if the technology could advance to support that application, Greg. We all know any kind of innovation to help wounded vets lead a normal and functional life is well worth it.
Prosthetic limbs and other artificial body parts have come a long way in the last 10 to 20 years, and many on the market and under development today can restore nearly the same functions as the human body parts they’re replacing, or even improve them.