Oronasal Fistula

An oronasal fistula (ONF) is a pathological connection between the oral and nasal cavities, primarily observed in dogs, with rare occurrences in cats. This condition typically arises in dogs suffering from advanced periodontal disease in the upper jaw.


  1. Periodontal Disease: Prolonged periodontitis, especially around the maxillary (upper jaw) canine teeth, can lead to bone destruction between the tooth root and nasal cavity.
  2. Trauma: ONFs can result from traumatic events, such as chewing on sticks or bones, causing damage to the thin bone separating the mouth and nose.


  1. Chronic Sneezing: The presence of an ONF allows food and debris to enter the nasal cavity, leading to chronic irritation and triggering frequent sneezing.
  2. Nasal Discharge: Persistent nasal discharge is a common symptom, indicative of chronic infection in the nasal area.

Repair and Treatment

Repairing an oronasal fistula typically involves surgical intervention to address the opening and prevent further complications. The surgical procedure includes creating a flap of tissue composed of gingiva and mucosa, which is then used to cover the hole in the maxilla.

Surgical Procedure

  1. Flap Creation: A flap of tissue is generated, comprising gingival and mucosal components.
  2. Tissue Transposition: The flap is meticulously moved to cover the opening in the maxilla, re-establishing the separation between the oral and nasal cavities.
  3. Healing and Recovery: Post-surgery, it is crucial to allow the surgical site to heal without interference. Careful monitoring of the dog’s diet and the use of an Elizabethan collar are often employed to prevent inadvertent disruption of the surgical site.

Importance of Repair

Repairing an oronasal fistula is essential to alleviate chronic inflammation and discomfort in the nasal cavity. Left untreated, the continuous entry of food and debris into the nasal area can contribute to long-term health issues and affect the dog’s overall well-being.

Postoperative Care

  1. Dietary Considerations: Careful examination and adjustment of the dog’s diet to minimize interference with the healing process.
  2. Elizabethan Collar: The use of an Elizabethan collar helps prevent the dog from rubbing or disrupting the surgical site, ensuring a successful recovery.

Early diagnosis and prompt surgical intervention contribute to a more favorable outcome and improved quality of life for dogs affected by oronasal fistulas. Regular dental care and timely treatment of periodontal disease can play a crucial role in preventing the development of such complications.