Finally: Scientists perfect artificial sphincter

“The smooth muscle cells align themselves around the mould in a perfect, continuous circle,” says Khalil Bitar of Wake Forest Baptist Medical Center’s Institute for Regenerative Medicine in Winston Salem, North Carolina. Bitar led the research team while working at the University of Michigan Medical School in Ann Arbor. “The neural cells then innervate this structure and make filamentous structures and projections around it,” he says.