ICD-10-CM > S00-T88 > T20-T25 > T25 > T25.7 > T25.73 > T25.739 T25.739 Corrosion of third degree of unspecified toe(s) (nail) Non-Billable/Non-Specific Codes T25.739A..., initial encounterT25.739D..., subsequent encounterT25.739S..., sequela