Happy Meal toys like Transformer figurines and Hot Wheels cars have sparked joy with little kids for decades—and now, one of the designers behind the miniatures is changing lives for thousands of people. Dallas-based entrepreneur Nancy Hairston founded MedCAD, a surgical solutions company, in 2007—and in the decades since, its 3D-printing innovations have helped patients recognize themselves in the mirror again.

But before Hairston was building skull implants, she spent most of her career in the design world. When she graduated art school with a sculpture MFA from Loyola University in 1991, she had a rude awakening: She couldn’t find any open jobs for what she wanted to pursue. Meanwhile, 3D animation was all the rage at the time, so Hairston pivoted and took on a litany of modeling and animation jobs, from Mary Kay cosmetics to software company Alias. Eventually, she landed in the toy industry. The tactile practice of sculpting in clay was now being done digitally on a computer, which meant designing in 3D—and major corporations were wanting it to manufacture everything from toys to shoes.

“It was as if a lightning bolt hit me,” Hairston tells Fortune, speaking of the first time she entered the 3D-modeling world. “That was [all] the rage. That was the tool to use. So I started doing Happy Meal toys and Bratz toys for Mattel.”

However, the late 2000s changed things: The entrepreneur says her peers’ roles were all heading to Asia, leaving behind medical and aerospace work as the main points of entry in the U.S. Luckily, Hairston was already recognizing the potential for 3D modeling in healthcare—so she quit her “sensible” 9-to-5 job and launched MedCAD.

“It was thrilling and scary, but I saw the opportunity because the technology was so new,” Hairston recalls.

The call from a surgeon that changed Hairston’s life

She had already started tinkering with anatomy modeling, adapting the toy-development software she’d used for orthognathic surgery applications like jaw and teeth repairs. By the time 2009 came around, she built a business plan to get FDA clearance. And younger surgeons—who grew up exposed to advanced tech and 3D animation, Hairston says—were starting to take note as word spread of her innovations.

Then, Hairston’s phone rang. The ensuing call would alter the trajectory of her career.

“[I had] one of those pivotal moments in your life, where your whole world changes. I got a phone call from a surgeon that I knew, and he said, ‘Hey, you know, do you think you could make me a cranial implant?’” Hairston says. “And that’s how it started.”

MedCAD went on to fill the unmet needs of patients with small to large deformities stemming from trauma-related injuries or physical abnormalities. Skull implants have continued to be a huge part of the business, but the company has since expanded into other areas of the body such as foot, ankle, and facial reconstruction products, all conceptualized with 3D designs.

“We were some of the earliest people doing it,” Hairston continues. “There’s a fantastic thread to all of this is, that we are able to bring a person back as much as we can to a normalized state with a lot less surgeries. [Patients are] waking up with the ability to have teeth implants after they heal. That’s the power of this technology—we can do a more holistic approach to reconstructing a foot or a face.”

Scaling MedCAD to upwards of $20 million in annual revenue

Since founding MedCAD nearly two decades ago, the company has continued to grow in the 3D-implant space. The company tells Fortune it has achieved profitability and boasts an annual revenue estimated to be between $10 million and $20 million this year and in 2026, but did not specify exactly how much it’s making in annual profit. Cranial and neuro products are a key growth driver, experiencing 18% to 25% growth year-over-year since 2022. It’s also ramping up a direct-to-hospital strategy, but a majority of its revenue comes from long-term contracts with global medical leaders needing implants and medical devices.

Despite having a successful run in toy-designing and founding a profitable business, Hairston says she’s most energized by the difference her implants make in peoples’ lives. Sparking joy among little kids with her McDonald’s toys and Bratz dolls was one achievement, but she’s making even more waves for thousands of medical patients hoping to feel whole again.

“Toys are really fun for children, but they’re not played with for long,” Hairston says. “We can really make a difference making these kinds of products for humans that change their lives. That gave me a lot of the power and the passion to do it.”