When Maxine Kessler lost complete hearing in one ear four years ago, she avoided a surgical procedure to implant a rod in her skull that would help her hear. Now she’s able to hear again thanks to a new nonsurgical device that picks up sound vibrations from her deaf ear and transmits them to her good ear via a device that fits inside her mouth around her back teeth.

“I can hear very well from that ear,” said Kessler, whose sudden hearing loss was caused by an autoimmune disease. “But I can’t tell where the sound is coming from.”