3-D printing and surgery a 'paradigm shift'

New York — Zeesy Stern lay unconscious on an operating table at NYU Langone Medical Center as a surgeon removed a section of her jaw where a golf-ball-size tumor had begun to displace the teeth on the left side of her mouth. Another doctor, meanwhile, worked to extract a piece of her fibula that would be fitted like a puzzle piece into the space where her jaw once was.

The goal was to remove the growth and create a new, fully functioning jaw, a feat that once took three operations over 18 months and left some patients with trouble chewing and disfigurement. But the doctors at NYU Langone had pioneered a new approach, one they dubbed “jaw in a day.” The tool that made it possible: not a scalpel, but a 3-D printer.

“It's a paradigm shift in the way of doing surgery,” said Dr. Jamie Levine, chief of microsurgery at NYU Langone, and one of the surgeons who worked on Stern. “There was a need for it to be more precise.”

The Institute for Reconstructive Plastic Surgery at NYU Langone is one of a growing number of New York hospital departments that have embraced the use of 3-D printing, in which materials such as plastic or titanium powder are ­exuded, layer by layer, to create objects: jewelry, kitchen utensils or, say, a new trachea.

The surgeons at NYU Langone use the printers to better plan and execute complex procedures like Stern's with more precision and predictability, ultimately saving hours in the operating room and $20,000 to $30,000 per reconstruction.

Medical growth

The promise of 3-D printing is a world of science fiction come to life: Headlines from 2015 included the first 3-D-printed nose in the U.S., created by a doctor at the New York Eye and Ear Infirmary of Mount Sinai.

Last year also saw Food and Drug Administration approval for 3-D-printed pills and vertebrae. Designs for bionic hands are now available for free on the Internet, and researchers from around the world are experimenting with organs printed from living cells.

The genius of 3-D printing is that, unlike traditional manufacturing, complex objects are not more expensive to make; they do not require unique molds or multiple machines. The cost of any object is determined simply by the amount of printing material used and the time needed to design it on a computer.

Medical-grade printers are expensive, some costing upward of $200,000. But one printer can make an infinite number of objects customized to each individual's anatomy. And the cost of printers is starting to come down. A Philadelphia company called BioBots made waves last year by releasing a $10,000 bioprinter, which it offered for $5,000 to scientists for testing.

In Stern's case, her doctors designed a metal plate and plastic surgical guides — indicating where to cut or drill — based on a digital 3-D model of her skull made from CAT-scan images. The pieces were manufactured by 3D Systems, a South Carolina company whose founder, Chuck Hull, patented the first 3-D printer in 1986. Though 3D Systems would not disclose its costs, the plastic in each of Stern's surgical guides retails for just a few dollars.

“That's the whole secret of 3-D printing,” said Katherine Weimer, vice president of medical devices at 3D Systems. “Complexity is free.”

Despite the potential for innovation, medical 3-D printing, as Stern learned, is only just beginning to be adopted in New York. Stern received her initial diagnosis from an oral surgeon who was unaware of 3-D printing's advances, telling her that her only option was a lengthy, three-surgery ordeal. During much of that time, he said, Stern would be left with a seriously diminished set of teeth.

The prospect gave the usually calm 38-year-old special-education teacher an uncharacteristic dose of anxiety.

“If I could get through one surgery, I would still have to get through the next and the next,” said Stern, thinking back on the prognosis 18 months later in her apartment on the Upper West Side. “My life would have been destroyed for a long time.”

The cost of the machines is only one hurdle to wider adoption of 3-D printing. The learning curve of mastering the design software is steep, and doctors need to spend extra time planning the surgery and designing the tools they'll need to execute it.

The health industry is also mired in regulatory, cultural and institutional challenges that preclude rapid change. The pioneers in this field are finding that insurance companies, as well as patients and doctors, must be made to understand the value of 3-D-printed devices in order to factor them into reimbursement rates. A priority for 3D Systems is conducting studies with institutions to prove that 3-D printing can improve health outcomes and save money.

As doctors have found more uses for 3-D printing over the past decade, they have influenced the materials developed by companies such as 3D Systems and Stratasys, the parent company of Brooklyn-based MakerBot, which manufactures lower-cost desktop 3-D printers.

New materials

A few years ago, there were only plastics, which could be printed into custom prosthetics and manipulated into patient-specific surgical tools. Then, titanium powder was loaded into 3-D printers to produce custom implants. Now mixed materials are opening up new possibilities.

The Feinstein Institute for Medical Research on Long Island is experimenting with something MakerBot calls limestone. The material is actually a composite of organic plastic and calcium carbonate that together mimics bone. More flexible materials that can act as other body parts are also in the works.

To gain FDA approval, any 3-D-printed material or device that comes into contact with patients must be capable of being sterilized. It can be a challenging process.

“Some materials go through something in the 3-D printing process that makes them nonsterile,” said Weimer of 3D Systems. But she said FDA approval for 3-D printed products is becoming more common.

Some New York hospitals are hoping to speed up the pace of adoption — and plant the seed for more homegrown innovation — by creating in-house 3-D printing centers where experienced users can assist novices.

Within hospitals, 3-D printing capabilities can vary widely by department. Two medical units at NYU Langone have their own printers, while Levine and his team collaborate with 3D Systems, using the company's printers and software. Other departments don't use the technology at all.

Dr. Oren Tepper, director of craniofacial surgery at Montefiore Medical Center in the Bronx, has been using the technology since 2007 and, like Levine, outsources his printing needs to 3D Systems. Now, however, he is in talks with Montefiore about creating a 3-D printing center on-site that would be widely accessible to physicians at the hospital.

“I think the main limitation of 3-D printing is not functionality or cost but awareness of what can be done,” Tepper said. “The majority of health care workers don't even have the knowledge that this technology exists.”

Stern herself was only vaguely aware of 3-D printing before her diagnosis in March 2014 of a benign but fast-growing tumor called an ameloblastoma. While researching second opinions, she found Levine and his team of surgeons at NYU Langone and was soon buoyed by the doctors' confidence and the “after” pictures they showed her of previous patients.

Stern's jaw-in-a-day surgery began early one May morning in 2014. Her parents and sister bided their time in the waiting room as the surgical team removed her jaw and cut the bone from her leg.

Careful digital planning and the 3-D-printed cutting guides FedExed to them by 3D Systems allowed her doctors to work simultaneously, knowing that everything would match up in the end. The implant carved from her leg fit her jaw perfectly. The same was true of the titanium plate the surgeons had designed to hold Stern's new jaw in place.

Before 3-D printing entered the equation, there was a lot more “eyeballing,” according to Levine. He couldn't go into the operating room with a metal plate the exact size and shape he needed. Instead, he had to manipulate the standard pieces of metal he had on hand while the patient was sedated.

“As you can imagine, sitting in the O.R. with a set of pliers to make [the plate] fit the jaw is somewhat time-consuming,” said Dr. Daniel Ceradini, associate director of microsurgery at NYU Langone, who also helped develop the jaw-in-a-day procedure. If the placement of the plate or jaw implant were just a few millimeters off, the patient could suffer.

Into the jaw implant, the surgeons inserted the screws that would secure Stern's new dentures. For this, they used a drilling guide, which is really just a few centimeters of plastic that aids in the placement of a screw hole. Still, it's a piece of plastic that Levine and Ceradini insist makes all the difference by eliminating guesswork that could lead to costly complications.

When Stern left the operating room after 12 hours, disoriented because it was dark outside, her sister turned pale. “Is that Zeesy?” she asked her father. Stern's face was severely swollen. She had to spend a week in the hospital, being fed through a tube in her throat. Afterward, Stern spent two months at her parents' house, embarrassed to go outside because she had yet to receive her dentures.

Three months post-op, though, she was back at work. Despite the chunk of bone missing from her leg, she was running after the kids she teaches at a preschool near Central Park.

“It's always going to be a little stiff,” said Stern, touching her jawline. She has a faint scar on her throat where her feeding tube had been inserted, and a slight indentation to the left of her chin — both of which she has to point out to people for them to notice.

Since her surgery, Stern's doctors have continued to refine their methods. They are now able to fit a patient's dentures on the day of surgery. Soon, Ceradini said, the dentures will be 3-D-­printed as well.

Within a decade, Levine predicts, 3-D ­printers will be as common as CAT scans, which, in 1995, were just as novel as 3-D printers are now. His colleague Ceradini agrees. “Looking down the road 10 years, having a 3-D printer that's in the office or in the clinic will become the new mainstay,” he said, “as opposed to having one company that prints these things and FedExes them to you the next day.”