Background: Upper third molar exodontia is one of the most common and simple dentoalveolar surgical procedures. Complications, such as bleeding from the posterior superior alveolar vessels are rare but potentially dangerous.
Methods: This article describes a case of postoperative hematoma of the temporal and infratemporal fossa after simple upper third molar extraction.
Results: The etiology of this uncommon complication could be rupture of the posterior superior alveolar vessels during injection of the local anesthetic. The absence of concomitant tearing of the periosteal envelope overlying the maxillary tuberosity may force blood backwards and upwards along the external pterygoid muscle into the infratemporal fossa and further along the anterior border of the temporal muscle. In two previously reported cases, the hemorrhage spread up into the infratemporal fossa and through the inferior orbital fissure into the orbit. In the case described here the bleeding stopped spontaneously; nevertheless, inpatient observation was indicated because of the possibility that a retrobulbar hematoma might develop.
Conclusion: Uncomplicated upper third molar extraction is one of the most common procedures of oral and maxillofacial surgery but can nevertheless trigger unexpected late complications, such as bleeding into the deep skull spaces. In such cases referral to an oral maxillofacial surgeon is essential for appropriate follow-up and management.