Oroantral fistulas are a pathological communication between the oral cavity and the maxillary sinus (antrum).
The term oroantral fistula is similar to but not synonymous with the term oroantral communication (OAC). An oro-antral fistula refers to an "epithelialized" pathological unnatural communication between the oral cavity and the maxillary sinus. It develops when the oro-antral communication fails to close spontaneously, remains patent and becomes epithelialized .
There is a slightly greater male predilection .
Oroantral fistulas may be subtyped by location into:
- alveolosinusal fistula
- palatalosinusal fistula
- vestibulosinusal fistula
They can result from a number of reasons:
- following posterior maxillary tooth extraction (most commonly molar)
- following radiation therapy
Typically seen as a disruption or defect involving the bony floor of the maxillary sinus with soft-tissue opacification or fluid involving the ipsilateral sinus.
Treatment and prognosis
Oroantral fistulas <2 mm wide usually heal without intervention, larger fistulas may require surgery .