That's good to hear, certainly. Hearing aids can assist when hearing diminishes with age, or other effects that affect the sensitivity of the hair cells in the cochlea.
For those who have have lost their hearing in the fashion as being described here, however, i.e. overnight, typically the auditory nerve has sustained irreparable damage, and thus no hearing aid will ever help because it's not the sensor that's necessarily damaged, but the "wiring" between the sensor and the brain, if you will.
This is sort of where cochlear implants come in...