Oronasal Fistula (ONF)

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Oronasal Fistula (ONF)

Oronasal fistulas are a communication between the oral cavity and the nasal sinus. One of the most common sites for an oronasal fistula is in the area of the maxillary canines. If the fistula is located more toward the middle or the back aspect of the upper jaw, it can be referred to as an oroantral fistula.

Sometimes the tooth is present with an oronasal fistula and sometimes the tooth has fallen out or was extracted and the gum tissue did not heal properly.


This abnormal communication should be closed surgically to prevent infection of the nose and in severe cases, this could lead to pneumonia.