In what’s being hailed as a world first in regenerative medicine, five children have received new ears grown from their own cells.

The children, living in China and ranging from age 6 to 10, were all born with microtia, a birth defect where at least one ear is underdeveloped. Traditional treatments for the condition involve either surgically attaching a synthetic ear or forming an ear from cartilage harvested from the patient’s ribs.