Hearing loss is cumulative and irreversible.
...and preventable.
I wear hearing plugs, without exception, whenever I anticipate a chance of gunfire. Substantial hearing loss in my left ear is a result of my not doing so when a 7 mag went off nearby.
I double up with foam plugs / muffs at the range, and put in plugs upon arrival at the property, even before loading my rifle. Slim Shady gave me a pair recently with an attached cord that are very useful; a backup pair of plugs stays in my pocket.
Because I am not retired, and in the medical realm, I have to make every effort to protect whatever hearing is left:
"Bad news, Mrs. McGeever, I couldn't hear your husband flatlining on the ICU monitor. On the upside, I ran a box of 220 grain through my 30.06 yesterday and it's dead on at 100 yards!"