ICD-10-CM > S00-T88 > T20-T25 > T25 > T25.6 > T25.63 > T25.631 T25.631 Corrosion of second degree of right toe(s) (nail) Non-Billable/Non-Specific Codes T25.631A..., initial encounterT25.631D..., subsequent encounterT25.631S..., sequela