Question about regeneration of OHC in mammal

[Lee, Sangjae]

Dear all

I am hard of hearing due to sensorineural hearing loss. According to the 
recently publication, auditory hair cells may have the ability to 
regenerate and function after considerable damage. However, I have heard 
that there is no good evidence for regeneration in the mammalian 
cochlea, probably because of the way the cells are arranged. 

What relationship between regeneration and cell arrangement?
Relevant paper or other reference are welcome.

Thanks for your help.

Sangjae