3-D printing – The OM Blog by Heizer, Render, & Munson

OM in the News: 3-D Printed Homes and Disaster Areas

A SoLa Impact modular housing unit is assembled at a Los Angeles factory

After Jerry Camarillo’s home in Altadena, Calif., burned down, he was determined to rebuild the ranch house exactly as it was before the L.A. wildfires. But the home’s insurance policy would cover only a fraction of the $700,000 estimated cost to rebuild. Then he found Hapi Homes, a company that builds prefabricated homes as pieces in factories and then assembles them on-site. The company could build his home for $200,000 less than the cost of traditional construction, and do it in less than half the time.

Companies that use modular construction, 3-D printing or other nontraditional methods have existed for decades on the fringe of home building, often tainted by previous missteps. (Off-site factory home construction has historically been used for lower-budget homes, leaving many people with the preconception that it tends to be of lesser quality). Now, these firms are breaking into the mainstream by offering a faster and less costly alternative for rebuilding in cities ravaged by natural disasters, reports The Wall Street Journal (June 3, 2025).

An ICON system uses 3-D printing to add concrete to the framing of a home

Many of the thousands of displaced homeowners in L.A., Hawaii and the Southeast are giving these businesses a look. Victims of hurricanes, wildfires or other disasters can be desperate to rebuild, but their insurance payouts are often well short of what is needed to cover traditional construction costs. Will disasters be the turning point for the wider adoption of factory-built housing?

ICON, a company that makes 3D-printed homes, uses giant 3-D printers to squeeze layers of concrete into the framing for a house. Reframe Systems builds homes in robotic, artificial-intelligence-powered microfactories. Offsite-factory construction can accelerate the building process because fewer workers are required and materials are often purchased in bulk. The shorter timeline can sharply reduce carrying costs for a project. And in disaster areas, where many builders are competing for construction labor and materials, factory-home manufacturers have an edge because they can access less crowded supply chains in other cities and states.

Classroom discussion questions:

How do 3-D printing and factory home-building differ?
What did an industry CEO meant when he said: “Never let a crisis go to waste?”

OM in the News: 3-D Printing and the Future of Global Manufacturing

Now that much of the hype around 3-D printing has died down—no more of that 2010s-era talk about a Star Trek-style replicator in every home—a funny thing is happening to this technology. It’s becoming a widely used, and in some respects quietly revolutionary, update to the way that people manufacture and process things we rely on every day—from cars to industrial machinery to food. “What’s more, the way this technology is being used could have implications for the shape of global supply chains to come,” writes The Wall Street Journal (Jan. 14-15, 2023).

A quick refresher from Chapter 5 (see p. 290): 3-D printing, also known as “additive manufacturing,” generally works by adding tiny layers of material—usually powdered metal or plastic—one at a time to form an item, and fusing them with binding agents, lasers or other methods. Thus, parts are “grown” instead of forged, cast, molded, or machined as in traditional manufacturing. Just a decade ago, this kind of manufacturing was, with rare exceptions, suitable only for creating prototypes. What’s different now is that newer technology lets these systems print objects strong enough to be used in finished products—and relatively quickly.

Cadillac Celestiq’s new “ultra-luxury” $300,000+ vehicle has more than 100 3-D printed parts

Recently, for example, GM made 60,000 weatherproof seals using 3-D printing, in plastic, rather than making them the old-fashioned way, to make sure it could deliver its 2022 Chevy Tahoe on time. BMW is making broad use of 3-D-printed parts throughout its lineup. Mercury Marine is producing its newest V12, 600-horsepower outboard motor with 3-D-printed molds.

3-D printing is making rapid inroads into conventional manufacturing all over the world. Globally, the entire industrial additive-manufacturing market grew to $13 billion in 2022, from $5.7 billion in 2016. That growth should accelerate in the next 5 years, with the size of the industry reaching $37 billion by 2026, as industrial 3-D printing displaces traditional mass manufacturing.

Companies can also use 3-D printing to do away with some of their inventory of spare parts, many of which can sit on warehouse shelves for years. Both Caterpillar and Saudi Aramco, for example, are digitizing their libraries of old parts so that they can print them in 3-D as needed, when machines that may have working lives of decades break. During the pandemic, Caterpillar began using some 3-D printed parts, made in the U.S., in place of conventionally manufactured versions that had become difficult to import from India.

Classroom discussion questions:

Explain the concept of “additive manufacturing.”
Why does the new Cadillac have so many printed parts?

OM in the News: 3-D Printed Homes Are Sprouting Up

A rendering of the Lennar community of 3-D printed houses near Austin, Texas

A major home builder is teaming with a Texas startup to create a community of 100 3-D printed homes near Austin, gearing up for what would be by far the biggest development of this type of housing in the U.S.

Lennar Corp. and construction-technology firm Icon are poised to start building at a site in the Austin metro area. While Icon and others have built 3-D printed housing before, this effort will test the technology’s ability to churn out homes and generate buyer demand on a much larger scale.

If 3-D printing succeeds at this more ambitious level, it could offer a response to America’s chronic shortage of homes for sale, especially in the affordable price range, writes The Wall Street Journal (Oct.27, 2021). Mortgage-finance company Freddie Mac estimated that the national deficit of single-family homes stood at 3.8 million units at the end of 2020.

The vast majority of newly built single-family homes in the U.S. are constructed on-site and framed in wood using traditional construction methods. Icon’s 3-D printed houses use concrete framing instead. Its 15.5-foot-tall printers can build the exterior and interior wall system for a 2,000-square-foot, one-story house in a week. The printer squeezes out concrete in layers, like toothpaste out of a tube. The machines can print curved walls, allowing for more creative house designs.

Lennar will complete the houses using traditional construction methods. The week it takes Icon to print a wall system is about the same amount of time it takes to frame and drywall a home using traditional construction methods, but Lennar plans to speed up that process in the future. 3-D printed homes can also be built more cheaply and with less waste compared with typical newly built houses. Icon requires only three workers on-site when printing a wall system, replacing as many as 6 to 12 framers and drywall installers needed for conventional construction.

Classroom discussion questions:

What are the advantages of 3-D printed home construction?
The disadvantages?

OM in the News: 3-D Printing Hobbyists to the Rescue

Owen Plumb helped start a group in Alberta that has printed 1,000 face shields.

Practically overnight, 3-D-printing enthusiasts have remolded their home-based hobby into an emergency production line for scarce personal protective equipment for front-line workers, writes The Wall Street Journal (June 9, 2020).

Thousands of volunteers have banded together on several continents to help in the face of the pandemic crisis. Some 8,000 members of a British design group called 3D Crowd UK have printed parts for more than 170,000 face shields using 3-D printers in their homes. The group also arranges for the face shields’ assembly and distribution to hospitals and other health organizations in Britain.

The group is just one of a growing number of supply chains to spring up in Britain, the U.S. and Canada, staffed by 3-D-printing hobbyists and entrepreneurs helping to make PPE for health-care and other front-line workers. The groups illustrate the potential for harnessing the power of distributed manufacturing to deliver products on a large scale. Such community-driven approaches are “incredibly agile and well-suited to respond quickly to local needs'” says a U. of Cambridge prof.

Before Covid-19, Owen Plumb, 13, who lives in Alberta, Canada used his 3-D printer to create robots and toy-rocket parts. In March, Owen helped create a local group that has now 3-D-printed 1,000 face shields, many of which have been distributed to front-line essential workers at a local hospice and to other institutions lacking PPE. Likewise, the nonprofit Glia Project in London, Ontario, has provided roughly 5,000 face shields to small and midsize hospitals and clinics around Canada. And at Michigan State University, one professor has helped organize a group of 40 people who have printed 8,000 face shields for health-care workers in Michigan.

Classroom discussion questions:
1. What are the strengths of 3-D printing (often called additive manufacturing). Hint: see Chapter 7, p.295 of your OM text.

2. What are the downsides of this grass roots system?

OM in the News: The Next Israeli Breakthrough May Be a 3-D Printed Heart

This photo at the University of Tel Aviv shows a 3D print of heart with human tissue.

“The future is here,” one shopper remarked to another at a Tel Aviv market after watching the TV report that Israeli scientists unveiled a 3D print of a heart with human tissue and vessel. Calling it a first and a “major medical breakthrough” that advances possibilities for transplants, scientists hope one day to be able to produce hearts suitable for transplant into humans as well as patches to regenerate defective hearts.

The heart produced by researchers at Tel Aviv University is about the size of a rabbit’s. It marked the first time anyone anywhere has successfully engineered and printed an entire heart replete with cells, blood vessels, ventricles and chambers, reports The Times of Israel (April 19, 2019). The researchers plan to transplant them into animal models in about a year. “Maybe, in 10 years, there will be organ printers in the finest hospitals around the world, and these procedures will be conducted routinely,” said the project leader.

Their work involved taking a biopsy of fatty tissue from patients that was used in the development of the “ink” for the 3D print. Using the patient’s own tissue was important to eliminate the risk of an implant provoking an immune response and being rejected. Challenges that remain include how to expand the cells to have enough tissue to recreate a human-sized heart.

Current 3D printers are also limited by the size of their resolution and another challenge will be figuring out how to print all small blood vessels. But while the current 3D print was a primitive one, larger human hearts require the same technology. 3D printing has opened up possibilities in numerous fields, provoking both promise and controversy.

Classroom discussion questions:

Name five other major breakthroughs in technology out of Israel.
Have other body parts been “printed”?

OM in the News: The 3-D Printed House

The printer can print walls with a maximum height of 8½ feet and a width of up to 28 feet, with no limits on length.

A Texas startup says it will be able to use a 3-D printer to churn out a concrete house within days by year-end, a technology that has the potential to help solve housing shortages, writes The Wall Street Journal (March 12, 2019). The firm, Icon, says the printer can produce bungalows of up to 2,000 square feet, nearly as large as the typical 2,400-square-foot American home. A year ago, Icon built a 350-square-foot home in Austin using the new technology.

Still, home builders are likely to face skepticism about the look of the new houses, which are poured one layer at a time, producing walls that resemble the folds of a shar pei dog. The technology faces other practical hurdles. Scaling up the production and shipment of expensive and heavy machinery is formidable. Building homes in windy, rainy, hot or cold conditions presents another test.

The new 3-D printer is operated by a tablet and requires only a few people to run and supervise it. The 3,800-pound machine squeezes out a stream of concrete as though it is icing a cake. The machine replaces workers who frame a home and install sheet rock, insulation and exterior finishes. It also produces less waste than a traditional construction site, where a third of materials end up in the trash.

Icon said it costs about $20,000 and takes several days to 3-D print a 2,000-square-foot house. After factoring in the cost of land and other construction such as plumbing and finishes, it works out to a reduction of about 30% in total costs. In Austin, where the average home is roughly $400,000, Icon said it could make a home $120,000 cheaper. A 3-D-printed home could address real problems facing the industry. Construction costs have skyrocketed due to shortages of workers and rising material prices.

Classroom discussion questions:

Why is the industry skeptical about 3-D printing’s widespread use?
What are the advantages of the approach from an OM perspective?

OM in the News: 3-D Printed Homes

“3-D printing is scaling up,” writes The Wall Street Journal (April 2, 2018). All over the world, an impressive diversity of people and organizations, ranging from startups to construction and engineering firms, are successfully prototyping 3-D-printed buildings. Prototype single-family dwellings have been 3-D-printed in China, Italy, Russia—and Texas. Global infrastructure firm AECOM uses 3-D printing to prefabricate jail cells and hospital rooms.

The technology is still nascent and it isn’t about to disrupt the $10 trillion global construction market. But the technology looks like it can save energy, materials and time. CLS Architetti in Milan has just finished 3-D-printing an 1,100-square-foot, single-family dwelling, using a portable concrete 3-D printer.

Using traditional methods, El Salvador’s People Helping People has already built more than 800 homes for families who previously lived in single-room shanties made of timber and sheet metal. Currently, a cinder-block house requires about 15 days and $6,500 to build. Printing a home instead is projected to take 24 hours, cost $4,000 and use half as much iron rebar.

Fundamentally, 3-D printing with concrete is a modern update of incredibly old building technologies. Worldwide, our prehistoric ancestors made homes from mud, adobe, cob and similar materials, building up their walls one layer after another. Their structures shared many of the same advantages of modern 3-D-printing: They were strong, cheap, locally sourced and minimized waste.

While concrete is by far the most widespread architectural-scale additive-manufacturing material, it isn’t the only one. In France, a home has been printed out of both concrete and foam. Researchers elsewhere are attempting architectural-scale building with cellulose, glass and a variety of novel composite materials.

Classroom discussion questions:

What are the advantages and disadvantages of using 3-D printing to construct buildings?
Is this technology really going to change the construction industry?

OM in the News: Industrial Firms Embrace 3-D

GE's Additive Development Center in Cincinnati — GE’s Additive Development Center in Cincinnati

A typical reaction a few years ago—when a wave of hype about 3-D printing’s promise had yielded little but a niche market of prototypes, toys and novelty items mostly for consumers– is no longer the case in industrial manufacturing. “The application of the technology to industrial parts has shifted 3-D printing from the theoretical into the practical in high-tech fields like aerospace,” writes The Wall Street Journal (Nov. 12-13, 2016).

General Electric recently agreed to buy two European 3-D printing-machine manufacturers, Sweden’s Arcam and Germany’s SLM Solutions Group, for more than $1 billion. GE sees 3-D printing with metal alloys, which it calls “additive manufacturing,” as an important part of its future, especially for its $25 billion jet-engine business.

The interior of the GE engine’s fuel nozzle is being made entirely through printing, and the company built a $50 million 3-D printing factory in Auburn, Ala., to make the parts in bulk for the new engines. GE has 28 of the machines in use at the Auburn facility and plans to have more than 50. It will produce 6,000 fuel nozzle injectors at the facility this year, and double output next year. GE says it can make a set of 9 of the fuel nozzle interiors in 5 days, rather than the weeks it takes using conventional techniques.

GE says 35% of the company’s new advanced turboprop engine will be made using 3-D printing, a technique that has allowed the company to eliminate more than 800 parts from the engine, cutting 5% of the engine’s weight. Printing metal parts makes it easier to build complex structures inside the walls of a part and eliminates multiple stages of casting and welding.

Classroom discussion questions:

What is additive manufacturing?
What are the advantages and disadvantages of industrial 3-D printing?

OM in the News: Reebok Starts Reshoring

“Sports equipment manufacturer Reebok is bringing some of its shoemaking back to the U.S., unveiling plans to open a new manufacturing lab next year using innovative liquid material and 3-D drawing,” reports IndustryWeek (Oct. 24, 2016). Some parts of the shoes planned will come from Asia, but the most technical components will be manufactured in Michigan.

German chemical giant BASF developed with Reebok a liquid material that is drawn across the outsole of the shoe for a three-dimensional fit with the help of 3-D drawing. The material helps absorb shock. “This is the very first use of this process to make athletic footwear. We borrowed and enhanced it from a process we found in the automotive industry,” said a Reebok executive. “The Liquid Factory concept is proprietary to Reebok.”

All of Reebok’s shoes were previously made in Asia.

In the short term, Reebok will only produce a small series of the shoes at the relatively high price ($189) due to still expensive development costs. In the long term, Reebok hopes to use this technology to create a product with competitive prices. “The Liquid Factory process is very flexible in that each machine can be used to create as many different concepts as imagination allows — it’s programming, not molds,” Reebok explained. “Scaling up is a matter of installing more Liquid Factory machine setups. The local manufacturing also gets us much closer to the consumer in terms of speed to market.”

Reebok is not alone in localizing production. In May, Germany’s Adidas announced it was opening a production site operated mostly by robots in the city of Ansbach, due to begin mass production next year. An Adidas site is due to open next year in the US.

Classroom discussion questions:

Why is Reebok reshoring some of its production? Why not more?
Explain the Liquid Factory concept.

OM in the News: Hospitals Printing 3-D Hearts to Help in Surgeries

A 3-D printed model shows cross sections of a child's heart — A 3-D printed model shows cross sections of a child’s heart

The night before operating on 2-year-old Myla Kramer, her surgeon held a copy of her heart, produced on a 3-D printer, in his hands. He studied it, trying to determine how to patch the many Swiss-cheeselike holes in the bottom of her heart — a potentially life-threatening condition. The next day, he knew exactly what to do. The surgery was a success, and Myla is thriving. Without the 3-D printed heart, said Dr. Mark Plunkett, “There was a significant possibility that I would get in there, try to patch over this area, and not necessarily get all of the holes.”

Congenital heart defects are problems with the structure of the heart at birth. They’re the most common type of birth defect, affecting 8 out of every 1,000 newborns. The printed hearts can help doctors in tricky cases such as Myla’s, writes the Chicago Tribune (Oct. 23, 2016). Engineers typically take an MRI or CT scan of a patient’s heart and run the scan through computer programs that allow them to print plaster composite hearts in 3 dimensions. The process for Myla took 2 days at the R&D arm of the OSF HealthCare Hospital in Peoria. Jump’s 3-D printer cost $80,000.

With use of 3-D printed heart models expected to grow, OSF (a chain of 10 Illinois hospitals) and the National Institutes of Health (NIH) are partnering with the American Heart Association to improve the quality of printed hearts, with the goal of helping more patients. The groups want to create an online database of 3-D printed hearts from patients with congenital heart defects, reviewed by experts in the field. The idea is to help standardize the process of printing hearts. Practitioners, medical students and others would be able to download the models at no charge and print them or view them in 3-D using virtual reality tools. The Tribune article also links to a 50 second video describing the process.

Classroom discussion questions:

How else can 3-D printing be used in medical care?
How are manufacturers now using the technology?

OM in the News: GE Buys Up 3-D Printing Companies

In a bold move to acquire technology that could transform factory production in the coming decades, General Electric announced it will spend $1.4 billion buying two European makers of 3D printers to expand use for the manufacture of components like aircraft parts. The biggest maker of aircraft engines said its first jet engine parts, called fuel nozzle interiors, made with the technology were introduced into service in July, paving the way for wider use.

The global market for 3D printing, also known as additive manufacturing, is growing as companies like GE increasingly move toward commercial parts production from making prototypes, writes Industry Week (Sept.6, 2016). The aviation industry was one of the early adopters because it allows for more complex designs, helping to lower the weight of parts and cutting back on waste of expensive materials on factory floors. GE Aviation has said it expects to print more than 100,000 parts for its jet engines by 2020. Companies are now starting to use them to actually produce parts, buying bigger numbers of machines.

3-D printers build an object by thinly layering materials such as plastic powder, metal or liquid resin, following instructions from a computer-drawn blueprint. They are used to make components including car parts and surgical implants. GE’s fuel nozzles made using 3D printing are the best known example of the use of the technology in the industry, but airplane makers Boeing and Airbus are also working on the process. Airbus is starting to incorporate 3D-designed parts on a test basis and says plane content produced with the technology will grow substantially in the coming years.

Classroom discussion questions:

What are the advantages of 3D printing of parts?
Describe the current status of 3D printers for business and personal use.

OM in the News: Chattanooga’s 3-D Hub

3-D Ops printed heart valve — 3D Ops printed heart valve

“Chattanooga faced a moment in truth in 1969 when Walter Cronkite declared the city to the most polluted in the nation,” writes Industry Week (Jan. 27, 2016). But the city cleaned up its toxic plants so much that by the mid-1980’s Nissan and GM set up shop and brought advanced technology to the area. With the growth of the auto industry and its supply chain, the region gained high tech manufacturing capability and was designated as an advanced tech area by the U.S. Over the past few years, the city has become a hub for 3D printing. The backbone of the growth of this sector is the city’s gigabit internet network, the most advanced smart grid system in the nation. This network provides the speed necessary for 3D printers.

“The availability of a variety of 3D printers, some so new that they aren’t even on the market yet, is a big draw for our company,” explains the CEO of 3D Ops. That firm uses CT scans and MRIs to build 3D printed models of body parts (such as an aorta valve), so that surgeons can better plan medical procedures. 3D Ops converts an MRI to a 3D printable file, then prints it for an average of only $400. The models provide surgeons with a more accurate approach to simulated surgery, decreasing the overall amount of time spent in the operating room. The surgeons are able to practice on physical models of body parts they will operate on.

Another 3D company, Branch Technology, recently introduced 3D printed interior walls. The company uses the world’s largest freeform 3D printer to print cellular matrixes out of ABS plastic, and then reinforces those structures with carbon fiber. They then use whatever material needed for a particular project to create the exterior of the walls. The technology necessary for the 3D companies to thrive was brought about by an aggressive plan that resulted in the city becoming America’s first “Gig City” with a citywide gigabit (1,000 Mbps) Internet service.

Classroom discussion questions:

Why did Chattanooga attract 3D printing firms?
Compare the region to other clusters noted in Chapter 8.

OM in the News: German Robots to Make Adidas Running Shoes in 2016

A German factory operated largely by robots is making its debut this year as the sportswear company seeks to cut labor costs and speed up delivery to fashion conscious consumers. Adidas had shifted most of its production from Europe to Asia and now relies on more than 1 million workers in contract factories, particularly in China and Vietnam. But Adidas now wants to bring production back closer to its major markets to meet demands for faster delivery of new styles and to counter rising wages in Asia and higher shipping costs, reports Reuters.com (Dec.19, 2015).

The new “Speedfactory,” near its Bavarian headquarters, will produce a running shoe that combines a machine knitted upper and springy “Boost” sole made from a bubble filled polyurethane foam. “An automated, decentralized and flexible manufacturing process… opens doors for us to be much closer to the market and to where our consumer is,” said the CEO.

Adidas currently makes about 600 million pairs of shoes and items of clothing and accessories a year, with a target of 900 million by 2020. The new factory will still use humans for parts of the assembly process. Around 10 people will be on the ground for testing purposes during the pilot phase, but Adidas is working towards full automation.

Almost 75% of Adidas sales currently come from products newer than 1-year-old and that figure is rising. “Our consumers become more challenging and demanding,” the CEO said. “Customization to markets and individuals will become the norm.” The ultimate objective would be to get replicas of red shoes worn by rapper-turned-designer Kanye West at a concert into the store the following morning. Adidas is also seeking to find ways to remove machine tools from the manufacturing process as they can take weeks to prepare. It has already used 3-D printing to create futuristic looking soles made from webs of crisscrossed fibers.

Classroom discussion questions:

Why the move to Europe?
Discuss the implications of mass customization at Adidas.

OM in the News: Exciting New Changes in 3-D Printing

The promise of 3-D printing is the ability to produce a solid part on the spot based on any digital 3-D file. While some of the highest end machines can precisely print small batch items such as hearing aids and artificial joints, the vast majority of 3-D printers in use today are slow and capable of making only trinkets and small prototypes. The early hype around 3-D printing peaked a couple of years ago, and now shares of the two big publicly traded printer manufacturers, Stratasys and 3D Systems, are 80% off their highs. But Carbon3D, a California startup, is reinjecting excitement into the field with a new way to print objects in 3-D quickly and precisely, writes Forbes (Nov.23, 2015).

Most 3-D printers use a technique known as fused deposition modeling, which is basically a hot-glue gun controlled by a robot arm that zig-zags back and forth depositing layers of plastic to make a solid object. A Carbon3D machine pulls a solid object from a small tub of liquid plastic–akin to the way the killer robot in Terminator 2 lifted itself out of liquid-metal puddles. It’s a variation on a decades-old technique called stereolithography, or the use of light to solidify liquid plastic. Carbon3D can produce objects of higher resolutions at speeds 25 to 100 times faster than traditional stereolithographic printers. Because the action of the machine is so smooth, it allows manufacturers access to a wider variety of performance materials such as stretchy elastomers and high-temperature-resistant resin.

A dozen companies, including Ford Motor and Hollywood studio Legacy Effects, are testing Carbon3D machines, each of which will cost about $10,000. Legacy, which worked on the Iron Man and Avengers movies, uses it to print prosthetics and props. The studio cut the time it took to print one crucial job from 16 hours to 2 hours.

Classroom discussion questions:

Why did 3-D printing peak a few years ago?
How does Carbon3D’s product change printing?

OM in the News: 3-D Printers and Human Organs

Atala's 3-D bioprinter. His 2011 TED talk on bioengineered organs has been viewed more than 2 million times. — Atala’s 3-D bioprinter. His 2011 TED talk on bioengineered organs has been viewed more than 2 million times.

At Wake Forest U.’s Institute for Regenerative Medicine, Dr. Anthony Atala’s research group is pushing the bounds of 3-D printing, with the goal of using that technology to replace human organs that fail, reports Smithsonian (May, 2015). The team works with custom-built bioprinters, powerful machines that operate in much the same way as standard 3-D printers: An object is scanned or designed using modeling software. That data is then sent to the printer, which uses syringes to lay down successive coats of matter until a three-dimensional object emerges. Traditional 3-D printers tend to work in plastics or wax. What’s different in this lab the capability to print something that’s alive.

The machine in the photo has a frame of heavy metal, with transparent walls. Inside are 6 syringes arranged in a row. One holds a biocompatible plastic that, when printed, forms the interlocking structure of a scaffold—the skeleton, essentially—of a printed human organ or body part. The others can be filled with a gel containing human cells or proteins to promote their growth. The external structure of the ear is one of the first structures that Wake Forest has tried to master, as a stepping stone toward more complicated ones. Staffers have implanted bioprinted skin, ears, bone, and muscle on laboratory animals, where they grew successfully into the surrounding tissue.

The number of 3-D printers in medical facilities is expected to double in the next 5 years. The trials are a harbinger of a world where patients order up replacement parts for their body the same way they used to order a replacement carburetor for their car. Atala claims we are getting close, with “simple” organs like skin, the external ear, the tube-like trachea. At the same time, he likes to envision a vast bioprinting industry capable of cranking out big and complex organs without which the body would fail, like the liver or the kidney. Such an industry could make traditional transplants completely obsolete.

Classroom discussion questions:

1. Why is 3-D printing so important to the future of medicine?

2. How is 3-D printing being used today in advancing manufacturing?