T23.72 - Corrosion of third degree of single finger (nail) except thumb T23.7 - Corrosion of third degree of wrist and hand T23.72 - Corrosion of third degree of single finger (nail) except thumb T23.721 - Corrosion of third degree of single right finger (nail) except thumb T23.722 - Corrosion of third degree of single left finger (nail) except thumb T23.729 - Corrosion of third degree of unspecified single finger (nail) except thumb