Difference between permanent and temporary wilting is as follows:

In temporary wilting, plants lose turgidity when rate of transpiration is more than rate of water absorption from the soil but in temporary wilting, wilting of the plant occurs and is a permanent phenomenon as the soil is unable to meet water requirement of the plant.

In temporary wilting, the plant regains turgidity when water requirement is met whereas in permanent wilting, the damage occurred is permanent causing eventual death of the plant.