ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.7 > T23.72 > T23.729 T23.729 Corrosion of third degree of unspecified single finger (nail) except thumb Non-Billable/Non-Specific Codes T23.729A..., initial encounterT23.729D..., subsequent encounterT23.729S..., sequela