The neurologist said that it was possible the nerve might regenerate/repair itself, but that if Charlie (the dog) started to chew on the paw then amputation was the best recommendation.
I agree with this. The nerve will either regenerate and heal, or it won't. As far as I know, there is no way to heal or repair nerves.
If it doesn't the dog will chew it because it has no feeling and he thinks it's some kind of foreign object stuck to him.
Sorry this happened!