oro-antral fistula

anatomy

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July 1, 2026

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An oro-antral fistula is an abnormal passageway that forms between the maxillary sinus and the mouth. The maxillary sinuses are large, air-filled cavities within the bones of the upper jaw. These sinuses are located above the roots of the upper teeth. If the roots of the upper teeth extend into the sinus cavity, or if tooth extraction damages the sinus floor, an opening can form, creating an oro-antral fistula. This condition can lead to symptoms such as diarrhea, incontinence, dehydration, or abdominal pain, depending on the location of the fistula.12

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sinus
Paranasal air sinuses
…between mouth and sinus (oro-antral fistula). The maxillary sinuses reach their maximum size by about age 12, when all the permanent teeth except the third molars have erupted. The nerves supplying the upper teeth run through the front wall of the sinus and may be irritated during acute antral…
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…between mouth and sinus (oro-antral fistula). The maxillary sinuses reach their maximum size by about age 12, when all the permanent teeth except the third molars have erupted. The nerves supplying the upper teeth run through the front wall of the sinus and may be irritated during acute antral…
Read More