The posterior deep temporal artery is a branch of the second part of the maxillary artery, which arises in the infratemporal fossa. This artery supplies blood to the temporalis muscle, a key muscle involved in mastication.
Location
The posterior deep temporal artery originates from the maxillary artery within the infratemporal fossa. It travels superiorly, deep to the temporal fascia, and courses along the temporal fossa on the deep surface of the temporalis muscle. It ascends alongside the anterior deep temporal artery, another branch of the maxillary artery, and both arteries provide blood supply to different parts of the temporalis muscle. The artery lies deep to the temporal muscle fibers, running close to the skull.
Anatomy
Origin
The posterior deep temporal artery originates from the second part of the maxillary artery, which is a major branch of the external carotid artery.[1] The maxillary artery has three parts, with the second part being located in the infratemporal fossa, a region beneath the zygomatic arch and lateral to the pterygoid muscles. The posterior deep temporal artery arises from this portion of the maxillary artery and ascends to supply the temporalis muscle.
Course and Pathway
Infratemporal Fossa
The posterior deep temporal artery arises in the infratemporal fossa, an anatomically complex space that houses several important structures, including branches of the maxillary artery, the mandibular nerve, and pterygoid muscles. The artery originates from the lateral aspect of the maxillary artery and immediately begins its ascent toward the temporal fossa.
Ascending Pathway
After originating from the maxillary artery, the posterior deep temporal artery ascends through the infratemporal fossa. It travels deep to the temporalis muscle, along the temporal fossa on the surface of the temporal bone. As it ascends, it remains deep to the muscle fibers of the temporalis, running between the muscle and the temporal bone, ensuring its supply to the deep portion of the muscle.
Relationship with Surrounding Structures
The posterior deep temporal artery runs in close proximity to several key structures:
- Maxillary artery: It is a direct branch of the maxillary artery, one of the terminal branches of the external carotid artery.[2]
- Anterior deep temporal artery: The posterior deep temporal artery often runs parallel to the anterior deep temporal artery, which also arises from the maxillary artery. Together, these arteries supply different parts of the temporalis muscle.
- Temporalis muscle: The posterior deep temporal artery runs deep to the temporalis muscle, providing a direct blood supply to its posterior portion.
- Zygomatic arch: As the artery ascends, it passes deep to the zygomatic arch, which forms the lateral boundary of the temporal fossa.
Branches
The posterior deep temporal artery gives off small muscular branches as it travels through the temporal fossa, providing blood supply to the temporalis muscle. These branches penetrate the deep surface of the temporalis muscle, ensuring that the entire muscle is well-vascularized. The artery itself may also have minor branches that anastomose with neighboring arteries, including branches of the superficial temporal artery.
Anastomoses
The posterior deep temporal artery forms important anastomoses with other arteries in the temporal and infratemporal regions. These include:
- Anterior deep temporal artery: The posterior deep temporal artery anastomoses with the anterior deep temporal artery, which supplies the anterior portion of the temporalis muscle. This anastomosis ensures that the entire temporalis muscle has a consistent blood supply from both arteries.[3]
- Superficial temporal artery: The posterior deep temporal artery may also form anastomoses with branches of the superficial temporal artery, a terminal branch of the external carotid artery. This connection helps maintain the blood supply to the temporal region and the temporalis muscle.
- Middle meningeal artery: There may be minor anastomotic connections with the middle meningeal artery, another branch of the maxillary artery that supplies the meninges and dura mater.
Distribution
The posterior deep temporal artery primarily supplies the temporalis muscle, a large, fan-shaped muscle responsible for elevating and retracting the mandible during mastication. The artery delivers oxygenated blood to the deep portions of the temporalis muscle, ensuring the health and functionality of the muscle fibers. It also contributes to the vascular network of the temporal fossa, nourishing the surrounding soft tissues and bones.
Relations with Temporalis Fascia and Temporal Bone
The posterior deep temporal artery runs deep to the temporalis fascia and on the surface of the temporal bone. As it travels through the temporal fossa, it maintains a close relationship with the bony structures of the skull.[4] Its deep course within the muscle protects it from injury during chewing and jaw movements, and its proximity to the temporal bone allows it to contribute to the vascular supply of the bone itself.
Variations
The anatomy of the posterior deep temporal artery is generally consistent, but variations can occur in its size, branching pattern, and relationship with surrounding structures. In some individuals, the artery may arise slightly higher or lower along the maxillary artery, or its branches may anastomose differently with nearby arteries. The size of the artery may also vary depending on individual anatomy, with larger arteries contributing more significantly to the vascular supply of the temporalis muscle.
Function
The posterior deep temporal artery is primarily responsible for providing a blood supply to the temporalis muscle, which plays a critical role in mastication (chewing). The artery also contributes to the vascular network of the temporal fossa and adjacent regions, ensuring the health and functionality of these structures. Below is a detailed description of the artery’s functions.
Blood Supply to the Temporalis Muscle
One of the primary functions of the posterior deep temporal artery is to supply the posterior portion of the temporalis muscle, a large muscle involved in movements of the mandible during chewing and biting.
- Muscle Function: The temporalis muscle is essential for elevating and retracting the mandible, actions that are necessary for biting and grinding food. The posterior deep temporal artery ensures that the muscle receives a sufficient supply of oxygenated blood, allowing it to perform these movements efficiently.
- Muscle Health and Vitality: The artery provides blood to the deep fibers of the temporalis muscle, ensuring that the muscle remains healthy and maintains its contractile strength.[5] The constant delivery of oxygen and nutrients prevents muscle fatigue and ensures the proper function of the muscle during prolonged periods of mastication.
Support for Jaw Movements
Through its blood supply to the temporalis muscle, the posterior deep temporal artery plays an indirect role in supporting the movements of the jaw, particularly the mandible.
- Elevation of the Mandible: The temporalis muscle is one of the primary muscles responsible for the elevation of the mandible, which is necessary for closing the mouth and applying pressure during chewing. The posterior deep temporal artery ensures that the muscle has the blood flow it needs to perform these movements consistently and without fatigue.
- Retraction of the Mandible: The posterior fibers of the temporalis muscle, which are supplied by the posterior deep temporal artery, are specifically involved in retracting the mandible—a backward movement important for aligning the teeth after biting. The artery’s blood supply supports the continuous function of these fibers, enabling smooth jaw movements.
Blood Supply to the Temporal Fossa
In addition to its role in supplying the temporalis muscle, the posterior deep temporal artery contributes to the vascular network of the temporal fossa, a shallow depression on the side of the skull that houses the temporalis muscle.[6]
- Temporal Bone Nourishment: As the artery runs along the surface of the temporal bone, it provides branches that supply the periosteum (the outer layer of the bone), ensuring that the bone remains healthy and strong. This blood flow supports the maintenance and regeneration of bone tissue, which is essential for the structural integrity of the skull.
- Soft Tissue Support: The artery also provides blood to the soft tissues surrounding the temporalis muscle, including connective tissue and fascia. This ensures that the entire region remains well-nourished and capable of supporting the muscle during mastication.
Collateral Circulation and Anastomoses
The posterior deep temporal artery forms important anastomoses with other arteries in the region, creating a network that ensures adequate blood flow to the temporalis muscle and adjacent structures.
- Anastomosis with Anterior Deep Temporal Artery: The posterior deep temporal artery anastomoses with the anterior deep temporal artery, which supplies the anterior portion of the temporalis muscle.[7] This anastomosis ensures that the muscle receives blood from multiple sources, providing a consistent supply of oxygen and nutrients even if one artery is compromised.
- Contribution to Collateral Circulation: The artery also forms smaller anastomoses with other vessels, such as the superficial temporal artery, which supplies blood to the superficial layers of the scalp and face. This network of collateral circulation helps maintain blood flow to the entire temporal region, ensuring that the temporalis muscle and surrounding tissues remain well-vascularized even under conditions of injury or reduced blood flow.
Support for Healing and Tissue Repair
The posterior deep temporal artery plays an essential role in healing and tissue repair following trauma or surgical interventions in the temporal region.
- Muscle Regeneration: If the temporalis muscle is damaged due to injury or surgery, the artery delivers the necessary nutrients and oxygen for tissue repair and regeneration. The consistent blood supply supports the recovery of muscle fibers and helps restore normal function.
- Bone Healing: In the event of a fracture or injury to the temporal bone, the artery contributes to the healing process by supplying blood to the periosteum and bone tissue.[8] This blood flow is essential for the formation of new bone and the overall recovery of the bony structures of the skull.
Support for Mastication and Jaw Health
Through its supply of blood to the temporalis muscle, the posterior deep temporal artery indirectly supports mastication and jaw health. The muscle movements supported by the artery’s blood supply are critical for:
- Chewing Efficiency: By ensuring that the temporalis muscle remains strong and functional, the posterior deep temporal artery helps maintain efficient chewing, allowing for the breakdown of food during mastication.
- Jaw Alignment: The retraction of the mandible, supported by the posterior temporalis muscle, helps maintain the proper alignment of the jaw and teeth during and after chewing. Proper blood flow from the artery ensures that this function is carried out smoothly, contributing to overall jaw health.
Clinical Significance
The posterior deep temporal artery is clinically significant due to its role in supplying the temporalis muscle and adjacent structures. It is crucial during maxillofacial surgeries and dental procedures that involve the temporalis muscle or the temporal region. Damage to this artery during surgery can result in excessive bleeding and may affect the blood supply to the temporalis muscle, leading to muscle weakness or delayed healing.
This artery is also important in procedures such as temporal fossa surgeries, craniofacial reconstructions, or treatments of temporal bone fractures, where its location must be carefully considered to avoid complications. Additionally, the artery’s anastomoses with other arteries in the temporal region contribute to the overall vascular network, making it an essential vessel for maintaining proper blood flow to the temporal region and jaw.