ETIOLOGY AND PATHOGENESIS These lesions occur secondary to a rupture of a salivary duct resulting in the spillage of mucin into the surrounding soft tissue1. The most common cause of the rupture is trauma1,5,6. Trauma can be blunt (e.g. hit by a car), sharp (e.g. gunshot), or foreign body (e.g. foxtail) in origin. In addition, it is not uncommon for these to occur after oral surgery (extraction, oral fracture repair, or neoplastic excision) due to transection of a salivary duct7. There are numerous cases however, in humans and animals with no history of trauma1,6. Sialoceles can also result from blockage of the duct by mucin, sialoliths, or inflammation3. Finally, there is one report in which dirofilariasis was the suspected cause8. The spilled mucin elicits an inflammatory reaction in the surrounding tissue and creates increased swelling. In general, the mucin pools ventral to the site of rupture.