Lifelike Artificial Ears Now Shaped by 3D-Printer
Artificial replacement ears are now fabricated with the help of 3D printing, which allows a much faster and precise process to create human ears that look and act like real ears, according to a study by researchers from Cornell University published on February 20.
Such lifelike artificial ears are important for children born with ear deformities or people who have lost all or part of their ear in an accident or from cancer, said the scientists working on the project.
A new ear is not actually printed directly, but is cartilage grown over a period of 3 months. But to get the exact shape, a 3D model is taken from an intact ear, and then turned into a mold using a 3D printer. A special high-density, injectable gel made of living cells (collagen) is injected into the mold, which is subsequently becoming newly grown cartilage.
“It takes half a day to design the mold, a day or so to print it, 30 minutes to inject the gel, and we can remove the ear 15 minutes later. We trim the ear and then let it culture for several days in nourishing cell culture media before it is implanted,” said co-lead author Lawrence Bonassar, associate professor of biomedical engineering at Cornell.
The artificial ears made this way are nearly identical to natural ears, according to the researchers who published their work online in the journal PLoS One.
"We trim the ear and then let it culture for several days in nourishing cell culture media before it is implanted," Bonassar said.
Weill Cornell associate professor Jason Spector added that physicians could reduce the likelyhood of rejection by using human cells from the same patient to build the ear.
Microtia, a condition where the external ear is not fully developed, occurs in about 1 to four per 10,000 births each year in the United States. Although children born with the deformity often have an intact inner ear, they lose hearing due to the missing external structure.
Currently, many artificial ears are made with materials that have a Styrofoam-like feeling. Surgeons can also build ears from a patient’s rib, but this is challenging and painful for children and the ears rarely look completely natural or perform well, according to the study authors.
If tests go well and prove the safety and effectiveness of the prosthetic, the first human implant of this new type of artificial ear could take place in as soon as three years, the Cornell team said.