When cancer researcher Rosalie Sears, PhD, clicks the print button, ink does not spray onto a page. Instead, actual human cells issue from different heads of her 3-D printer.

In a short while, she has before her a very small tumor -- an exact replica of a patient's cancerous growth. At that point, she and her colleagues can attack the printed copy with any number of cancer treatments.

"The hope is that it will allow us to test, in real time, how a patient's tumor will respond," says Sears, a professor of molecular and medical genetics at Oregon Health and Science University in Portland.

Sears's work is just one exciting aspect of 3-D printing's potential impact on medicine -- from prosthetics, to the bioprinting of cells, to lifelike models of organs, to the possibility of printable, implantable tissue.

Creating tailor-made robotic arms and hands is one of the more publicized uses of 3-D printing in health care. Volunteers working with free software available online have designed some of these devices. Such prosthetics are more functional than traditional ones, often at a tiny fraction of the cost. Think $50 vs. $30,000.

"It's more accessible than ever before," says Terry Yoo, PhD, a computer scientist and 3-D printing specialist at the National Institutes of Health. "Today, people are falling over their feet trying to come to the lab to do 3-D printing."

And this is just the start, says Cornell University associate professor of engineering Hod Lipson, PhD, author of Fabricated: The New World of 3D Printing. "The range of materials is expanding, the cost of machines is dropping, and we just keep seeing more and more applications. We haven't seen the least of it yet."

Pediatric cardiologist Matthew Bramlet, MD, has already witnessed the benefits of 3-D printing at Children's Hospital of Illinois in Peoria, where he practices. There, surgeons prepare for and plan surgeries for children with complex heart defects with the help of 3-D models of their patients' hearts.

The result? More effective operations. In one case, the model helped surgeons come up with a different way to repair a 3-year-old's heart. The boy -- who was at first expected to live 20 to 30 years -- now might lead a normal life.

"The model allows us to pull [a heart] out of 2-D screen and actually hold it in our hands and evaluate it in a dimension we never had before," says Bramlet. "They are real game-changers."

At Children's National Medical Center in Washington, D.C., engineer Axel Krieger, PhD, also uses his printer to assemble lifelike models of patients' imperfect hearts, using them as both surgical guides and teaching tools. His team has made about 40 model hearts, but a big question remains: Do they improve surgical outcomes? It's too early to tell, Krieger says.

"These surgeries are really complex, and it's difficult to tease out exactly what effect the model has, because it's just one little step in the work flow."

Krieger predicts that they'll have a better idea by next year, after many more heart surgeries.

Cancer researcher Sears also welcomes the ability to go beyond the shortcomings of two dimensions.

"We can grow tumor cells on a plate in the lab, but that's not how a tumor cell exists in the body, and responses in 2-D don't mimic what we see in the clinic," she says. "That's why we have thousands of targeted therapies that look promising in the lab but don't pan out in clinical trials in patients."

Using mice -- a common tool in cancer research -- also has serious drawbacks. One of them is time. Sears says it takes 6 months to implant and grow a tumor in a mouse. For fast-growing cancers like pancreatic cancer, patients can't wait that long. Enter 3-D printing or, more accurately, bioprinting, because this involves human cells.

"Within two weeks, we can learn whether these printed tumors respond or don't respond to a given therapy," Sears says.

Another advantage: Sears can print numerous identical tumors at the same time, allowing her to test multiple drugs at once.

"It's very exciting, both in terms of potentially getting patients the right drugs sooner and in understanding how cancer cells communicate with other cells," she says. "It's more promising to me than anything else that's out there right now."

But she says much research still needs to be done. The big question: Will patients' tumors respond to drugs in the same way as the 3-D printed models?

To Lipson, research such as Sears's is just the first step in 3-D printing's most exciting direction.

"That's the ultimate: bioprinting, or printing with live cells," Lipson says. He predicts we'll start to go beyond model making within the next several years. The next stop: implantable 3-D-printed tissue.

"I think that that is where the future is," he says. "We'll climb the ladder from simple tissue such as cartilage and bone to complex, heterogeneous tissue all the way to functioning organs, which is the Holy Grail indeed."

Lipson thinks FDA approval for the first such procedures remains at least 5 years away, though lab and animal testing is ongoing.

Interesting ethical questions come with the advancing technology, he says. For example, if scientists can bioprint a new knee to replace one ravaged by arthritis, do you go with a copy of your old knee, or do you allow a computer to design you a better one? Can we rebuild or improve our bodies?

In the short term, Lipson says, we'll see more and more 3-D-printed synthetic implants, such as hip and other joint replacements, custom-shaped to improve how well they work. Unlike prosthetics, though, implants can be costly.

"They're already on the market, but they're fairly new and expensive," he says.

Lipson says new developments in 3-D printing will be determined by economics: "It's a question of funding and market priorities rather than purely a technical challenge."

But we should expect big things, he says. "This is just the beginning. There's a lot more to come. This is not just a hype cycle."

Slideshow: The Bionic Body

World's First 'Bionic Man'

Rex, short for "Robotic Exoskeleton," is a showcase of cutting-edge prosthetics and biomechanics packed into one functional electric body. He sees with retinal implants, holds things in working hands, and walks on sensor-driven legs. He also has a kidney, spleen, lungs, pancreas, and a battery-powered heart to pump blood that’s made from plastic. In short, he’s almost living proof that if our parts fail, we can get new ones.

A Robotic Skeleton

Ekso, the bionic exoskeleton, was built at the University of California, Berkeley. It’s used in rehabilitation centers worldwide to help people who’ve lost the ability to walk due to stroke, injury, or a condition like cerebral palsy. Battery-powered motors drive the legs and make up for the lost brain-muscle function. The suit’s maker is working with Children’s Hospital of Oakland, CA, to build a version for kids.

An Artificial Heart

Doctors already have the SynCardia artificial heart to use in patients awaiting a transplant -- some 1,250 of them nationwide. Paired with a backpack-sized driver that keeps it going, it allows people to move around, leave the hospital, go home, and get stronger while they wait. But the story doesn’t end there. The FDA just gave its maker the green light to see if the device could be a permanent fix in people for whom transplant isn’t an option.

Lifelike Prosthetics

Not only do today’s prosthetics work like the real thing, they also appear more real than ever, with cosmetic details like freckles, fingerprints, painted nails, hair, and even tattoos. They can also match skin tone. These lifelike products, makers say, not only help with movement, they may also mend some of the emotional trauma that comes with loss of a limb.

Smartphone Controlled Arms

Users can program up to 24 commands into their smartphones to help move the latest version of Touch Bionics’ i-limb. The gizmo works via myoelectric technology: Sensors detect tiny movements in your muscles, and a computer in your hand translates them into dozens of precise actions. German user Claudia Breidbach says the arm comes in handy in her hobby: competitive skydiving. The i-limb ultra revolution and other prosthetics are available from Touch Bionics.

Mind-Powered Prosthetic Arms

Les Baugh, who lost both arms in an electrical accident 40 years ago, became the first double shoulder-level amputee to wear and mentally control two modular limbs. He says the device gives him a level of freedom in movement he hasn’t known for decades. The new surgery reassigns nerves that used to control Baugh’s arms and hand, says Johns Hopkins Trauma Surgeon Albert Chi, M.D. The project is still in the early stages of development.

Ankle-Foot Replacement

This battery-powered ankle-foot prosthesis, built by an MIT professor who lost his legs, mimics lifelike motion and gives the user a more natural gait. The bionic foot moves upward and forward and adjusts to bumpy ground. High-tech knees and ankles combine electronics, mechanics, and biology to work like real joints. The system is sold under the name BiOM T2.

Thought-Propelled Robotic Leg

Zac Vawter, owner of the world's first thought-controlled bionic leg, can sit, stand, walk, and climb stairs at will. In fact, he climbed 103 floors of Chicago's Willis Tower. A computer reads electrical signals from muscles in his leg and data from the robotic limb. It decides which type of movement he wants to make, sends the command to his leg, and off he goes. The leg should be available for widespread use in 2018.

Highly Mobile Modular Arm

Fred Downs, Jr., past director of the U.S. Department of Veterans Affairs prosthetics division, got the Luke arm (named for the Star Wars character) to replace the one he lost to a land mine in Vietnam. The device lets users perform complex tasks by sensing muscle movements in the remaining limb. It's the same size, shape, and weight as a human arm. Plus it’s modular, so it can replace a lost hand, lower arm, or complete arm. It’s FDA-approved and in production.

A Hand That Can Feel

Denis Aabo Sorensen has a prosthetic hand like no other: His can feel what’s in it. Designed by Europe’s NEBIAS project, the hand has sensors that are linked to nerves in Sorensen’s upper arm. Now when he grasps an object, he can tell what it is -- a baseball, an egg, a cup -- even when he’s blindfolded. Researchers are still at work on this technology; it’ll be years before these hands hit the market.

Retinal Implants

For the first time in 30 years, Larry Hester can see his wife’s face. Maybe not in great detail, but enough to reach out and touch it. Hester is one of about 100 people worldwide to receive the Argus II system, a tiny camera mounted on a pair of glasses that sends images to a retinal implant via a small computer Hester carries with him. It won't restore his sight, but it can help him -- and others who’ve lost their vision due to retinitis pigmentosa -- tell light areas from dark.

Reviewed by Arefa Cassoobhoy, MD, MPH on January 09, 2015

Sources: Sources

This tool does not provide medical advice. See additional information: Disclaimer

© 2015 WebMD, LLC. All rights reserved.

Slideshow: How 3-D Printing is Changing Lives

A Helping Hand

Ana Del Hoyo-Quinones was born without a fully formed right hand. Surgeries didn’t help. But last year, e-NABLE, a nonprofit that matches people who need prosthetic limbs with volunteer 3-D printing experts, connected Ana's family to a mechanical engineer near her Colorado home. Clay Guillory and his team gave 31 hours of their own time to design, print, and assemble the plastic layers of Ana’s new hot-pink hand. The whole project cost just $50. After she learns how to write with it, Ana promises she’ll send Clay a thank you letter.

An All-New Skull

In 2014, Dutch surgeons at the University Medical Center Utrecht replaced the skull of a 22-year-old woman with a 3-D printed plastic dome. A rare disorder had caused the bone protecting her brain to thicken, which led to vision loss and severe headaches. It took doctors 23 hours to complete the surgery. It worked -- afterward, her vision returned and her headaches stopped.

A New Leash on Life

Derby was born with tiny forelegs and no front paws. Instead of going for a walk outside, he could only scoot along on soft surfaces. He did get one lucky break -- his foster mom worked for 3D Systems, which makes 3-D printers. With help from an expert, the company created prosthetics for Derby -- rubber-lined cups molded to fit his forearms and set atop curved bottoms. Now he runs 2 or 3 miles a day with his adoptive owners.

A Gift From Overseas

Stevenson Joseph was born without fingers on either hand, so he wasn’t able to play catch with friends at the orphanage in Haiti where he lives. When a Californian software engineer met Stevenson on a trip, he was moved. A few months later he’d designed and printed a new left hand. He shipped it to Haiti, where a medical team fitted it to Stevenson, making him the first person in his country to receive a 3-D printed prosthesis.

Building a Backbone

In August 2014, Peking University doctors printed and implanted the first 3-D vertebra into the spine of a bone cancer patient, a boy named Minghao. He'd had part of his cervical spine removed to treat a malignant tumor. The titanium implant has tiny pores so new bone can grow into it and hold it in place.

Noses and Ears, Quicker

It used to take a lot of time to make prosthetic soft tissue like an ear or nose: Take an impression, make a mold, hand-paint the piece, and fit it to the patient. Fripp Design and Research in the U.K. has streamlined that process. The company works off an image of the patient and uses a 3-D printer to make layers of lightweight material to create the right skin color and texture. The result: a lighter, more "wearable" nose -- made much faster than in the past.

Skin Today, Eyes Tomorrow

Scientists at INSERM (The National Institute of Health and Medical Research) in Pessac, France, have boosted the 3-D process. "Bioprinting" creates cells that actually form working tissues. So far, they've made top layers of skin, nails, and hair, all of which could be used to test beauty products and new medicines for safety. Next up: Create tissues found in the eye's cornea.

Hope After Head Injury

When Hu, a farmer in China, fell to the ground from the third floor of a building, he severely damaged his head and brain. Doctors had to remove a piece of his skull about the size of a smartphone. Surgeons at Xijing Hospital in Xi’an, 3-D printed a titanium mesh implant for the left side of Hu's head. His doctors hope the implant will help his brain heal so that he'll once again be able to speak and write.

Providing Care for a Country

In Columbia, 850,000 people live with disabilities, many as a result from armed conflicts. Almost half of these people are poor, and more than 100,000 are children. An artificial leg or arm can cost up to $20,000. But Icesi University student Juan Pablo Munoz created a 3-D printed leg made of a plastic. Not only can he make a new limb within hours, it costs only about $60 to produce.

A Lifesaving Breath

Garrett Peterson was born with a faulty windpipe and spent his first 18 months in a hospital, using a machine to breathe. But several times a day, he would turn blue from lack of oxygen and pass out, because his trachea wasn't sturdy enough to stay open on its own. His parents sought help from C.S. Mott Children's Hospital at the University of Michigan. Surgeons there modeled a 3-D printed splint to prop open the toddler's trachea. The flexible tube will keep Garrett's windpipe strong for years -- until his own is strong enough to take over.

No More Transplants?

Experts might one day be able to make 3-D printed organs from scratch instead of waiting to do a transplant. Scientists at MIT have found a way to stack and organize the many cell types that make up body tissues, like the structure with liver cells shown here. The unique process layers tiny "molds" of computer-generated images, which can then support living, growing cells.

Reviewed by Arefa Cassoobhoy, MD, MPH on January 08, 2015

Sources: Sources

This tool does not provide medical advice. See additional information: Disclaimer

© 2015 WebMD, LLC. All rights reserved.

Which body part can't be replaced or enhanced with a 3D printed implant?

You are correct!


The correct answer is: Testicular

We haven't heard of a 3D printed Achilles tendon -- not yet, anyway -- but everything else is on the list of 3D parts that doctors have printed and used.

We'll climb the ladder from simple tissue such as cartilage and bone to complex, heterogeneous tissue all the way to functioning organs, which is the Holy Grail indeed." -Hod Lipson, PhD, Cornell University