Impact of dental devices on cochlear implants.

A cochlear implant (CI) converts mechanical sound energy into electrical signals that can be delivered to the cochlear nerve of profoundly deaf patients. The purpose of this study was to investigate whether electromagnetic interference with the CI occurs during the operation of the electric pulp tester, apex locator, electrocautery unit, electrosurgery unit, or panoramic radiograph machine. A mastoidectomy and cochleostomy were performed on a cadaver, and a CI was implanted. The dental devices were used intraorally, and the implant's circuitry was tested after each trial. A second CI was implanted in a human skull, which was then exposed to 50 panoramic radiographs, testing the implant's circuitry after each exposure. The probability of damage to the CI by any of the devices was negligible, except for the electrosurgery unit operated at level 7, which destroyed the CI's circuitry. Therefore, although the other devices seem safe, it is recommended that the electrosurgery unit not be used on a CI patient.