Kelli Miller was holding her infant son, Luke, as he pawed at an odd-shaped object the size of a child's fist.
The 8-month-old boy, at Phoenix Children's Hospital for a recent checkup, was touching a plastic replica of his heart — made by a 3-D printer the size of a large copying machine. Doctors used that brightly colored model as a guide for a delicate surgery performed on the boy in September, two weeks after his birth.
That printer, a $50,000 machine from 3D Systems, was humming quietly as it made a model of another child's abnormal heart in a small room off the hospital's second-floor lobby.
"We honestly think it's a game changer in how we plan to fix these anatomical abnormalities," said Dr. Stephen Pophal, the hospital's pediatric cardiology division chief.
The 3-D printer has also been used to create a matching ear for a child born with only one, said Justin Ryan, a hospital consultant and Arizona State University research associate, who operates the equipment.
Three-dimensional printing, an evolving technology over the past quarter-century, has accelerated in recent years to the point that it is turning science fiction into reality, creating biomedical models, implantable body parts, dental crowns, hearing aids, Invisalign braces and even 3-D human liver tissue.
Also known as additive manufacturing and rapid prototyping, the technology can print a vast range of products, including customized eyeglass frames, jewelry, plumbing fixtures, car and airplane parts, architectural models and even homes. A Chinese company, WinSun, is using a very large 3-D printer to make small houses for about $5,000 each.
Other novel uses of the technology have emerged, such as printing logos on chocolate or making pizza. NASA awarded a $125,000 grant last year to a Texas company for development of a 3-D printer to make pizza and other foods for long-duration space flights.
3-D printers make items in a process similar to inkjet printers, with a mechanism tracking back and forth. But instead of printing ink on paper, the machines apply layer after layer of plastic, metals or other materials. Using a computer-aided-design or CAD file, the 3-D printers build layers of material to shape an object.
A May 1 industry report from Wohlers Associates estimated that the 3-D printing market of all products and services worldwide totaled $3.07 billion in 2013. That is up 34.9 percent over 2012, the highest growth rate in 17 years.
Wohlers has forecast growth to $7 billion in 2016 and $21 billion by 2020.
Meanwhile, low-cost 3-D printers have put the technology within reach of entrepreneurs, hobbyists and schools. Sales growth of printers costing less than $5,000 was up slightly more than 100 percent in 2013 from the previous year, said Tim Caffrey, co-author of the 276-page report with company President Terry Wohlers.
Medical advances with additive manufacturing are "breaking on a weekly or biweekly basis," Caffrey said.
For tiny Luke Miller, the 3-D printer at Phoenix Children's Hospital aided his doctors and saved him from one or more invasive procedures that have risks for newborns.
Plus, the model of his heart was helpful in explaining the surgical procedures to his parents. Luke was born at St. Joseph's Hospital with a pulmonary atresia, a congential malformation of the pulmonary valve.
Doctors were aware of the abnormality before he was born. They used data from a CAT scan to make a 3-D model of Luke's heart in red, blue and green, to delineate vessels and chambers. That helped the team, led by heart surgeon John Nigro, prepare their surgical strategy and operate on the infant a little more than two weeks after he was born.
For Luke's parents, the whole experience was frightening. But the replica heart helped them visualize how doctors would repair their newborn son's heart, Kelli Miller said.
"They absolutely took great care of him," she said. "I wouldn't have wanted him to go anywhere else."
Technology cuts costs
Because of the precision of the 3-D models, surgeons can be more efficient in the operating room, which cuts costs and reduces risks for patients, said Bruce Bradshaw, director of marketing for Stratasys, a leading 3-D printer manufacturer based in Minneapolis and Israel.
Since August, the UPS Store has been testing a Stratasys 3-D printer in San Diego and five other locations nationwide where consumers and entrepreneurs can order custom-made objects, including prototypes, promotional items and architectural models.
Staples Inc. a month ago announced it was offering 3-D printing services at stores in Los Angeles and New York using a 3D Systems printer. It also announced in May 2013 that it was one of the first major U.S. retailers to carry 3-D printers with the 3D Systems Cube model priced as low as $999.
Stratasys also has desktop 3-D printers through its MakerBot subsidiary, starting at about $2,000, that are within reach of hobbyists, Bradshaw said. Users can download designs from Thingiverse.com to make products.
He does not expect 3-D printers will be common in homes anytime soon.
"Your mom isn't going to have a 3-D printer."
But Bradshaw said he does think the printers will be increasingly available at retail stores.
A consumer will be able to e-mail a file to a store to print a personalized iPhone case, create eyeglass frames in hundreds of colors or make a specific plumbing fixture, he said.
Caffrey of Wohlers Associates agreed that it is more likely that 3-D print shops and major retailers will offer print services rather than average consumers having their own printers.
A lot of hobbyists make things like chess sets, Yoda figurines and other trinkets with their personal 3-D printers, he said.
"Once the novelty wears off, the printer gets pushed off into the corner like a treadmill that you end up hanging laundry on," Caffrey said.
Quartz, an online news site, recently quoted Charles Hull, a leading 3-D printing innovator, as saying there is a lot of hype about the potential of the technology but that he focuses on "the here-and-now and the near-term future."
Tempe firm a 3-D leader
Eric Miller of Phoenix Analysis & Design Technologies Inc. describes 3-D printing as being "like cake decorating."
"It takes 600 or 700 layers to make a mold of a running-shoe sole," said Miller, one of PADT's four owners with Rey Chu, Ward Rand and Mark Johnson.
They started the company in 1994 and have been profitable every year but the first one, Miller said.
PADT, based at the ASU Research Park in Tempe, is one of the largest resellers of 3-D equipment in the Southwest, and the company has 14 3-D printers that it uses for product development and rapid prototyping. It has 82 employees and offices in Albuquerque and Denver.
PADT's clients have included Honeywell, Intel, Raytheon, Freeport-McMoran, Orbital Sciences and Mayo Clinic.
Miller said 3-D printing emerged in the aerospace industry about 25 years ago to make prototypes and expanded to a wide range of industries as the technology got better and cheaper, with a wider range of plastics.
"The engineering world uses it to test fit, form and function," he said, whether it's for plastic bottles for consumer products or packaging.
3-D printing for surgical-kit packaging cut the prototype-development time down from 95 hours to five hours, Miller said.
Traditionally, the final prototype was used to make a mold or tooling for standard manufacturing. But that is changing.
There is a growing trend to directly produce parts using additive manufacturing or 3-D printing. Wohlers Associates' latest report showed that final-part production accounted for about 35 percent of the $3 billion spent in 2013 on 3-D printing and services. That is up from 28 percent in 2012 and 3.9 percent in 2003.
Caffrey of Wohlers said General Electric is using additive manufacturing for fuel nozzles on its jet engines and plans to make more than 30,000 of the parts in 2015.
The previous fuel nozzles, made with traditional manufacturing, had 18 parts welded together. The 3-D-printed parts are 25 percent lighter and five times more durable, he said.
Todd Grimm, an independent consultant with the Additive Manufacturing Users Group, said 3-D printing of parts is generally best for low-volume, high-value components, said.
The group, with roots that go back 26 years, has about 600 members and is growing. Its annual meeting in Tucson last month attracted 283 first-time attendees.
3-D printing has become an attention-grabbing technology in the past five years, but before that, people did not know what you were talking about if you mentioned the technology, Grimm said.
Public perceptions about additive manufacturing have been altered by headlines about proof-of-concept advances that seem like science fiction. Just as flying cars remain a cartoon fantasy, it's unlikely that anyone is going to be printing their own automobile anytime soon, he said.
A year ago, Texas law student Cody Wilson test-fired a plastic handgun that he made using a 3-D printer.
"A lot of this stuff, it's all possible, but is it probable and in what time frame?" said Grimm, arguing that the cost of the 3-D-printed gun would be well beyond the price of a comparable handgun made with traditional manufacturing.
Bio-printing liver tissue
Additive manufacturing is also useful for developing low-volume medical implants for hip and knee replacement, according to Grimm.
Mayo Clinic has used 3-D printing to make models of hip-replacement parts for its patients. Orthopedic surgeons make their own 3-D models to help guide them during operations, Mayo spokeswoman Lynn Closway said.
In the biomedical industry, San Diego-based Organovo Holdings Inc. announced late last month that it has started toxicity testing using its 3-D human-liver tissue for selected clients.
Its bio-printing technique uses "bio-ink" that contains liver cells that create tissue, using collagen to fuse the cells. The technology is not advanced enough to create a full organ, but tissue samples are perfect for testing drugs, according to Organovo.
The company also noted that Wake Forest University has adapted the bio-printing technology to put skin cells directly onto a wound.
Grimm, the Additive Manufacturing Users Group consultant, said it will be 10-20 years before medical science can 3-D "print" a human organ.
"You're not going to print yourself a new heart tomorrow," he said. "That's still science fiction, but it's not unrealistic to think it will be scientific fact in the not-too-distant future."