Temporalis muscle
Encyclopedia
The temporal muscle is one of the muscles of mastication
Muscles of mastication
During mastication, four muscles of mastication are responsible for adduction and lateral motion of the jaw. Other muscles, usually associated with the hyoid such as the sternohyomastoid, are responsible for opening the jaw.-Muscles:*The masseter...

.

Structure

It arises from the temporal fossa
Temporal fossa
The temporal fossa is a shallow depression on the side of the skull bounded by the temporal lines and terminating below the level of the zygomatic arch.-Boundaries:...

 and the deep part of temporal fascia
Temporal fascia
The temporal fascia covers the Temporalis muscle.It is a strong, fibrous investment, covered, laterally, by the Auricularis anterior and superior, by the galea aponeurotica, and by part of the Orbicularis oculi....

. It passes medial to the zygomatic arch
Zygomatic arch
The zygomatic arch or cheek bone is formed by the zygomatic process of temporal bone and the temporal process of the zygomatic bone , the two being united by an oblique suture; the tendon of the Temporalis passes medial to the arch to gain insertion into the coronoid process...

 and inserts onto the coronoid process
Coronoid process
The Coronoid process can refer to:* The coronoid process of the mandible, part of the ramus mandibulae of the mandible...

 of the mandible.

The temporal muscle is covered by the temporal fascia
Temporal fascia
The temporal fascia covers the Temporalis muscle.It is a strong, fibrous investment, covered, laterally, by the Auricularis anterior and superior, by the galea aponeurotica, and by part of the Orbicularis oculi....

, also known as the temporal aponeurosis.

The muscle is accessible on the temples
Temple (anatomy)
Temple indicates the side of the head behind the eyes. The bone beneath is the temporal bone as well as part of the sphenoid bone.-Anatomy:Cladists classify land vertebrates based on the presence of an upper hole, a lower hole, both, or neither in the cover of dermal bone which formerly covered the...

, and can be seen and felt contracting
Muscle contraction
Muscle fiber generates tension through the action of actin and myosin cross-bridge cycling. While under tension, the muscle may lengthen, shorten, or remain the same...

 while the jaw is clenching and unclenching.

Innervation

As with the other muscles of mastication, control of the temporal muscle comes from the third (mandibular) branch of the trigeminal nerve
Trigeminal nerve
The trigeminal nerve contains both sensory and motor fibres. It is responsible for sensation in the face and certain motor functions such as biting, chewing, and swallowing. Sensory information from the face and body is processed by parallel pathways in the central nervous system...

. Specifically, the muscle is innervated by the deep temporal nerves.

Blood supply

The muscle receives its blood supply from the deep temporal arteries
Deep temporal arteries
The deep temporal arteries, two in number, anterior and posterior, ascend between the Temporalis and the pericranium.They supply the muscle, and anastomose with the middle temporal artery....

 which anastomose with the middle temporal artery
Middle temporal artery
The middle temporal artery arises immediately above the zygomatic arch, and, perforating the temporal fascia, gives branches to the Temporalis, anastomosing with the deep temporal branches of the internal maxillary....

.

Actions

Contraction of the temporal muscle elevates the mandible. The somewhat horizontal fibers of the posterior part of the muscle retract the mandible.
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