What is a serious complication of an untreated dental abscess in the maxilla involving the canine space?

Maxillary dental abscesses, particularly from anterior maxillary teeth (canines), can spread via the canine space to the infraorbital space. The infection can then extend superiorly to cause periorbital or orbital cellulitis, presenting with periorbital swelling, erythema, proptosis, and restricted eye movement — a potentially vision-threatening emergency. Additionally, the angular vein connects the facial area to the ophthalmic vein, which drains into the cavernous sinus; this pathway can lead to cavernous sinus thrombosis, a rare but life-threatening complication. Ludwig's angina and parapharyngeal abscesses are more commonly associated with mandibular infections.