ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.7 > T23.72 T23.72 Corrosion of third degree of single finger (nail) except thumb Non-Billable/Non-Specific Codes T23.721Corrosion of third degree of single right finger (nail) except thumbT23.721A..., initial encounterT23.721D..., subsequent encounterT23.721S..., sequelaT23.722Corrosion of third degree of single left finger (nail) except thumbT23.722A..., initial encounterT23.722D..., subsequent encounterT23.722S..., sequelaT23.729Corrosion of third degree of unspecified single finger (nail) except thumbT23.729A..., initial encounterT23.729D..., subsequent encounterT23.729S..., sequela