"“Right on the border of Burma and Thailand, there are landmines like you wouldn’t believe,” he says. These landmines leave many residents as amputees, residents who “would typically never see a prosthesis because of [the] fitting and time it would take.” Armed with Physionetics’ technology and good will, Johnson went to Burma and fitted two amputees with the printed arms. “We donated them,” he says. “All I had to do is go out there, show them how it was fit, and within an hour and a half, we had them on these two guys.” Stories like this are what drive Summit to continue his quest for a “self-use viral app for developing countries” that can create prosthetics. “There will simply never be enough prosthetists to meet their needs.” This isn’t his dream for the future; he thinks it’s a scientific possibility now. And he strongly disagrees that the materials 3-D printing can handle aren’t strong enough to work as limbs. He points out that, “the [human] bones that we have are not as strong as titanium,” a material used in many prosthetic limbs. “When you have great flexibility of geometry, as we do with 3-D printing, you can overcome what strength you don’t have,” Summit says. He says he’s found a way to overcome this strength barrier by creating a hollow prosthetic, then filling it with a lattice structure, similar to the construction of a bird’s bone. “Nature’s been doing this for a long time,” he says."