Maxillary Artery Branches
The maxillary artery, a terminal branch of the external carotid artery, has three main subdivisions that supply the maxillary sinus region: the infraorbital artery, the posterior superior alveolar artery, and the posterior lateral nasal artery. 1
Primary Branches from the Maxillary Artery
The maxillary artery branches are typically organized based on their anatomical course through three regions:
Third Portion Branches (Pterygopalatine Fossa)
From the pterygomaxillary junction to the pterygopalatine fossa, the maxillary artery typically branches in the following order 2:
- Posterior superior alveolar artery - branches first, approximately 15.2 mm from the inferior point of the pterygomaxillary junction 2
- Infraorbital artery - branches second, approximately 32.2 mm from the pterygomaxillary junction 2
- Artery of the pterygoid canal - branches third 2
- Descending palatine artery - branches fourth, approximately 24.8 mm from the pterygomaxillary junction, which then divides into greater and lesser palatine arteries in 95.2% of cases 2
- Sphenopalatine artery - terminal branch 2
This branching sequence occurs in approximately 85.7% of individuals 2.
Clinically Relevant Vascular Anatomy
Maxillary Sinus Vascularity
The three main arterial subdivisions of the maxillary artery that supply the maxillary sinus are critical during sinus elevation surgery, as injury to these vessels accounts for most intraoperative bleeding complications. 1
Alveolar Antral Artery
The posterior superior alveolar artery and infraorbital artery form an important intraosseous anastomosis called the alveolar antral artery, which is present in 100% of cases within the lateral sinus wall 1. This anastomosis:
- Runs 11.25 to 26.90 mm from the alveolar crest (average 17.91 mm) 1
- Usually has a diameter less than 1 mm, though vessels greater than 2.5 mm have been described 1
- Causes intraoperative bleeding in approximately 10% of cases when diameter is 0.5-1 mm, but 57% of cases when diameter is 1-2 mm 1
Posterior Lateral Nasal Branches
The posterior lateral nasal branches arise from the sphenopalatine artery (itself a branch of the maxillary artery) and play an important role in vascularizing the medial wall of the maxillary sinus 1.
Anatomical Variations
The third portion of the maxillary artery demonstrates significant morphological variation 3, 2:
The bifurcation pattern between sphenopalatine and descending palatine arteries shows four types: Y-type (19%), intermediate (36%), M-type (17%), and T-type (28%) 3.
Clinical Implications
Surgical Considerations
Understanding maxillary artery anatomy is essential for safe transcatheter treatment, as some branches supply the dura mater and cranial nerves and can anastomose with the internal carotid artery, creating risk for intracranial complications. 4
Imaging Assessment
Computed tomography should be used preoperatively to assess the exact location of the alveolar antral artery prior to maxillary sinus augmentation procedures, given the high degree of variability in vessel pattern, course, and distance from the alveolar bone margin 1.