Hi Guest! 30600 – Repair fistula; oronasal J32.0 – Chronic maxillary sinusitis G50.1 – Atypical facial pain For the appeal, you will want to be sure to include your SOAP notes/clinical notes that shows the medical necessity. Patient medical history, your doctor”s exam/procedure notes, the diagnosis and treatment plan information should all be included. You may also consider to include in your appeal using the following diagnosis code to represent the oronasal fistula: M25.18 – Fistula, other specified site Hope this helps!