Temporalis muscle

Temporalis muscle is one of the muscles involved in mastication, or chewing. It is a broad, fan-shaped muscle located on the side of the skull, above and in front of the ear. The muscle is covered by the temporal fascia, and its fibers converge to form a tendon that inserts onto the coronoid process of the mandible, or lower jawbone.

Anatomy

The temporalis muscle originates from the temporal fossa and the deep part of the temporal fascia. It passes medial to the zygomatic arch and forms a tendon which inserts onto the coronoid process of the mandible, with its insertion extending into the anterior border of the ramus of the mandible.

The muscle is innervated by the deep temporal nerves, branches of the mandibular nerve (V3), which is itself a branch of the trigeminal nerve.

Function

The temporalis muscle is one of the four muscles involved in mastication. The others are the masseter muscle, the medial pterygoid muscle, and the lateral pterygoid muscle. The primary function of the temporalis muscle is to elevate the mandible, which closes the mouth. The muscle is also capable of retracting the mandible, which pulls the jaw backward.

Clinical significance

Due to its role in mastication, problems with the temporalis muscle can lead to difficulties with chewing. Temporalis muscle tension is also a common cause of temporomandibular joint disorder (TMJ), a condition that can cause pain and dysfunction in the jaw and surrounding muscles.

See also

• Mastication
• Muscles of mastication
• Temporomandibular joint disorder

Temporalis muscle

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  Anatomy of the temporalis muscle
• Face of man with hypertrophy of the temporal muscles
  Face of man with hypertrophy of the temporal muscles
• Animation of the temporal muscle
  Animation of the temporal muscle
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  Illustration of head and neck muscles
• Temporalis muscle
  Temporalis muscle