ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.7 > T23.71 > T23.712 T23.712 Corrosion of third degree of left thumb (nail) Non-Billable/Non-Specific Codes T23.712A..., initial encounterT23.712D..., subsequent encounterT23.712S..., sequela