A bone-anchored hearing aid (BAHA) is a surgically implanted device designed to treat hearing loss by transmitting the sounds it receives through direct bone conduction to the nerve fibers of the inner ear. The device consists of an externally worn receiver and sound processor, which resembles a standard behind-the-ear hearing aid, and an external abutment that vibrates a titanium implant. The hearing aid is operational once the titanium fixture bonds with the surrounding tissue (osseointegration). This process usually takes two to six months from when the device has been implanted, but has been dramatically reduced by Oticons new minimally invasive surgical procedure.
Standard hearing aids require specialized batteries, typically zinc-air, in order to function. These batteries must be replaced by the user or an audiologist. Virtually all hearing aid batteries sold on the market are zinc-air. They have a high energy density that is achieved by using the oxygen in the air as the cathode portion of the cell. This eliminates the necessity to package a cathode electrolyte in the cell, allowing for more effective current-generating volume for the same amount of space.