teo_audio
I hope your last post was "tongue-in-cheek. At least I think. Damage to inner ear hair cells (nerve) is permanent and irreversible. If said hearing loss is caused by nerve damage.
Not a joke, not tongue in cheek. Look at the link....
https://www.sciencedaily.com/releases/2017/08/170807120530.htm
Even newer (mo'better newest news):
https://www.sciencedaily.com/releases/2017/11/171116132800.htm
(Paraplegic rats walk and regain feeling after stem cell treatment The rats show significantly improved mobility and sensory perception, as well as spinal cord healing)