ICD-10-CM > S00-T88 > T26-T28 > T28 > T28.5 T28.5 Corrosion of mouth and pharynx Non-Billable/Non-Specific Code First (T51-T65) to identify chemical and intent Codes T28.5XXA..., initial encounterT28.5XXD..., subsequent encounterT28.5XXS..., sequela