ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.6 > T23.63 > T23.631 T23.631 Corrosion of second degree of multiple right fingers (nail), not including thumb Non-Billable/Non-Specific Codes T23.631A..., initial encounterT23.631D..., subsequent encounterT23.631S..., sequela