ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.7 > T23.73 > T23.739 T23.739 Corrosion of third degree of unspecified multiple fingers (nail), not including thumb Non-Billable/Non-Specific Codes T23.739A..., initial encounterT23.739D..., subsequent encounterT23.739S..., sequela