--which means no further damaging processes, sufficient oxygen and nutrients, and the like, the figure usually given for nerve regeneration is around a millimeter each day. This would apply to all regenerating nerves--the body generally doesn't concentrate its efforts on one nerve tract to the exclusion of all others, and then, when that tract is "restored", shift to the next one.

What this means is that a fiber that begins in the dorsal root ganglia and reaches down to the fingers or toes might take years to reach its destination, if it ever does. Many people have nerve regeneration that is patchy or incomplete. And seldom do the nerves take the exact same route to their afferents that they occupied before; along the way the nerve growth cones have to fight through and around connective tissue, muscle and the like, so I think the millimeter/day estimation is fairly optimistic.