Temporalis: Difference between revisions

No edit summary
No edit summary
Line 13: Line 13:


=== Origin ===
=== Origin ===
Temporal bone, specifically the floor of the temporal fossa
Temporal bone, spanning from the temporal fossa to the inferior temporal line of the lateral skull.


=== Insertion  ===
=== Insertion  ===
Line 19: Line 19:


=== Nerve ===
=== Nerve ===
 
[[Trigeminal Nerve|Trigeminal nerve]] (CNV),  deep temporal branch of mandibular division (CNV3).
* ''Central part'': deep temporal nerves of the mandibular nerve
* ''Anterior part'': branches of the buccal nerve
* ''Posterior part'': branches of the masseteric nerve


=== Artery ===
=== Artery ===
Line 29: Line 26:
== Function ==
== Function ==


* Anterior fibres: Elevates mandible
* Anterior and middle fibers: Elevates mandible
* Posterior fibres: Retracts the mandible
* Posterior fibers: Retracts the mandible


== Clinical relevance  ==
== Clinical relevance  ==
Line 59: Line 56:


== Assessment  ==
== Assessment  ==
=== '''Manual Muscle Testing''' ===
'''Jaw closure (Mandibular elevation)'''<ref>Hislop, H. J., & Montgomery, J. Daniels and Worthingham's Muscle Testing: Techniques of Manual Examination. 8th ed. / St. Louis, Mo., Saunders / Elsevier. 2007.</ref>
* Muscles assessed: Temporalis, Masseter and Medial pterygoid
* Test: Patient clenches jaws tightly
* Manual Resistance: The chin of the patient is grasped between the thumb and index finger of the examiner and held firmly in the thumb web. The other hand is placed on top of the head for stability. Resistance is given vertically downward in an attempt to open the closed jaw
* Instructions to Patient: "Clench (or hold) your teeth together as tightly as you can, keeping your lips relaxed. Hold it. Don't let me open your mouth."
* Criteria for Grading
** Functional: Patient closes mouth (jaw) tightly. Examiner should not be able to open the mouth.
** Weak Functional: Patient closes jaw, but examiner can open the mouth with less than maximal resistance.
** Non Functional: Patient closes mouth but tolerates no resistance. The masseter and temporalis muscles are palpated on both sides. The masseter is palpated under the zygomatic process on the lateral cheek above the angle of the jaw. The temporalis muscle is palpated over the temple at the hairline, anterior to the ear and superior to the zygomatic bone.
** 0: Patient cannot completely close the mouth. This is more of a cosmetic problem (drooling, for example) than a significant clinical one.
''Note: In unilateral involvement, the jaw deviates to the strong side during attempts to close the mouth.''


== Treatment  ==
== Treatment  ==

Revision as of 15:42, 21 January 2024

This article or area is currently under construction and may only be partially complete. Please come back soon to see the finished work! (21/01/2024)

Original Editor - Carina Therese Magtibay

Top Contributors - Carina Therese Magtibay

Description[edit | edit source]

Temporal muscle lateral view.png

The temporalis muscle is one of the four primary muscles of mastication (chewing of food). It is a fan-shaped muscle with anterior fibres that have a vertical orientation, mid fibres have an oblique orientation, and posterior fibres have a more of horizontal orientation. [1]

Origin[edit | edit source]

Temporal bone, spanning from the temporal fossa to the inferior temporal line of the lateral skull.

Insertion[edit | edit source]

Coronoid process of the mandible

Nerve[edit | edit source]

Trigeminal nerve (CNV), deep temporal branch of mandibular division (CNV3).

Artery[edit | edit source]

Maxillary artery which is a branch of the external carotid artery.

Function[edit | edit source]

  • Anterior and middle fibers: Elevates mandible
  • Posterior fibers: Retracts the mandible

Clinical relevance[edit | edit source]

Masticatory muscle disorders to take note of:[1]

  • Myofascial pain and dysfunction. Most common etiologies myofascial pain and dysfunction of masticatory muscles:
    • Nocturnal bruxism
    • Habitual clenching of the mouth
    • Whiplash injuries during a trauma
  • Temporomandibular joint (TMJ) dysfunction
    • It can be caused by an imbalance of forces within the muscles of mastication. 
    • Nocturnal bruxism is a common cause of TMJ dysfunction.
  • Trismus aka Muscle spasm of the muscles of mastication
    • It can be a symptom of tumor or infection. An infection like tetanus may present with "lockjaw" or trismus.
  • Other infections or inflammation of the muscles may present as:
    • myositis
    • pain during the movement of the jaw.


Temporalis muscle is used for:[2]

  • Direct temporalis tendon injections
  • As a landmark for inferior alveolar nerve block anesthesia, third molar extraction, and determining posterior denture flange
  • Temporalis tendon transfers in plastic surgery

Assessment[edit | edit source]

Manual Muscle Testing[edit | edit source]

Jaw closure (Mandibular elevation)[3]

  • Muscles assessed: Temporalis, Masseter and Medial pterygoid
  • Test: Patient clenches jaws tightly
  • Manual Resistance: The chin of the patient is grasped between the thumb and index finger of the examiner and held firmly in the thumb web. The other hand is placed on top of the head for stability. Resistance is given vertically downward in an attempt to open the closed jaw
  • Instructions to Patient: "Clench (or hold) your teeth together as tightly as you can, keeping your lips relaxed. Hold it. Don't let me open your mouth."
  • Criteria for Grading
    • Functional: Patient closes mouth (jaw) tightly. Examiner should not be able to open the mouth.
    • Weak Functional: Patient closes jaw, but examiner can open the mouth with less than maximal resistance.
    • Non Functional: Patient closes mouth but tolerates no resistance. The masseter and temporalis muscles are palpated on both sides. The masseter is palpated under the zygomatic process on the lateral cheek above the angle of the jaw. The temporalis muscle is palpated over the temple at the hairline, anterior to the ear and superior to the zygomatic bone.
    • 0: Patient cannot completely close the mouth. This is more of a cosmetic problem (drooling, for example) than a significant clinical one.

Note: In unilateral involvement, the jaw deviates to the strong side during attempts to close the mouth.

Treatment[edit | edit source]

Resources[edit | edit source]

  1. 1.0 1.1 Basit H, Tariq MA, Siccardi MA. Anatomy, head and neck, mastication muscles.
  2. Yu SK, Kim TH, Yang KY, Bae CJ, Kim HJ. Morphology of the temporalis muscle focusing on the tendinous attachment onto the coronoid process. Anatomy & Cell Biology. 2021 Sep 1;54(3):308-14.
  3. Hislop, H. J., & Montgomery, J. Daniels and Worthingham's Muscle Testing: Techniques of Manual Examination. 8th ed. / St. Louis, Mo., Saunders / Elsevier. 2007.