Daniel Chae, Sid Bommakanti and Alan Tan won a $30,000 in college scholarships at the national finals of the Siemens Competition in Math, Science and Technology. (Siemens Foundation)
Three teens won a $30,000 prize for using a 3-D printer and stem cells from discarded teeth to design new dental implants.
The students, two from California and one from Virginia, presented their projects in Washington, D.C. last week in the 2015 national finals of the Siemens Competition in Math, Science and Technology. It's one of America's most prestigious science competitions for high school students, and winners are typically engaging in graduate level research.
"The level of projects coming forward is incredibly sophisticated," says David Etzwiler, CEO of the Siemens Foundation. "Many students have applied for or already received patents."
The Siemens Foundation started the competition in 1998 to encourage innovative scientific research before college.
"STEM education is happening in schools," says Etzwiler, "and we want to connect that to careers in science."
High school senior Daniel Chae, who is 18 and attends Thomas Jefferson High School for Science and Technology in Alexandria, Virginia, joined Bay Area 17-year-old seniors Sid Bommakanti, who attends Amador Valley High School in Pleasanton, and Alan Tan, who attends Irvington High School in Fremont. The young men are interested in medical careers and used their knowledge of stem cells as the backbone of their dental implant project.
As they were researching mesenchymal stem cells (MSCs)—cells that can turn into fat, muscle, cartilage or bone—they discovered that MSCs are found in dental pulp.
Dental pulp exists in all teeth but is thrown away when wisdom teeth are extracted.
The students wanted to make this "trash" useful.
"When we learned we could take stem cells from teeth—it’s actually part of medical waste—we realized could turn this into bone cells," says Tan.
The students first used a 3-D printer to create a scaffolding, or a tiny rectangular object the stem cells could grow on. They made the scaffold out of polylactic acid, which is solid at room temperature and comes from renewable sources like corn starch, tapioca roots, or sugar cane.
They then placed the dental pulp stem cells on the scaffolding, to see if bone cells would, in fact, grow.
They relied on the natural roughness on the scaffold to induce the bone cell growth, which is similar to what happens in humans.
Stem cells in our bodies must be stimulated, for example via hormones, to differentiate.
Knowing that changes in physical stimuli would cause stem cells to differentiate, the teen scientists wanted to see if the roughness of the scaffold would act as a type of physical stimulus.
Indeed that's what happened. The students noticed small clusters of cells growing on the scaffold. These nodule formations are an early sign of bone generation.
Ideally, the biodegradable 3-D scaffold could someday be implanted in people. Bone would grow on the model, becoming a dental implant, and the model would eventually disintegrate.
"The next step is to test it in the body," says Bommakanti. "But we need to do in vivo research in animals first."
The students worked at Stony Brook University's Garcia Center for Polymers at Engineered Interfaces for three months over the summer, testing their idea. They said the lab space and faculty guidance to support graduate-level research wasn't something they could find at their high schools.
Back at school in the fall, the students kept up the research and prepared for the competition.
"We actually missed a lot of school," says Tan.
It's not uncommon for the competitors to devote significant time and effort to their research.
"The students have each spent 1,500 or 2,000 hours working on these projects," says Eztwiler.
The grand-prize winner in the individual category, Maria Elena Grimmett, even started her research in 7th grade.
The Florida native developed a water purification method that uses small plastic beads to remove sulfamethazine, a common veterinary antibiotic.
Other competitors designed inexpensive wipes that can rapidly detect viral infections, software that screens for early-stage cancer, and bacteria that can be engineered into antibiotics.
"You read the paper every morning and shake your head and you think, how can I make this world better?" says Etzwiler. "These are the folks we’re going to hand stuff over to, and you realize we’ll be alright."
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