311 (Session 6) Muscles of the Face and the Scalp + Temporomandibular Joint and Muscles of Massifcation

What are the five layers of the scalp

• Skin

• Connective tissue

• Aponeurosis

• Loose connective tissue

• Pericranium

What is the occipitofrontalis connected by

Epicranial Aponeurosis

What is the frontal belly vs the occipital belly of the occipitofrontalis innervated by

Frontal belly: Temporal Nerve (CN VII)

Occipital belly: Posterior auricular nerve (CN VII)

• Both CN VII

What are the two parts of the orbicularis oculi muscle

Palpebral part

Orbital part

What is the orbicularis oculi muscle innervated by

Palpebral part: temporal nerve

Orbital part: zygomatic nerve

• Both CN VII

What is the main function of the palpebral part of the orbicularis oculi muscle

Closes the eyelids gently

What is the function of the orbital part of the orbicularis oculi?

Closes the eyelids tightly

Name this muscle, what nerve its innervated by, and main function

Name: Corrugator supercilii

Innervation: temporal nerve (CN VII)

Function: draws eyebrowns downward medially and downward (vertical wrinkles)

What are the three muscles of the nose and what are they all innervated by

1. Procerus

2. Levator Labii Superioris Alaeque Nasi

3. Nasalis

All innervated by the zygomatic nerve

• CN VII

What are the two movements involved in opening the TMJ

Rotation = initial / small mouth opening

Anterior translation = wide mouth opening

Name this muscle, innervation, and function

Name: Procerus

Innervation: Zygomatic nerve (CN 7)

Function: depreses medial ends of eyebrows and creates transverse wrinkles

What are the two parts of the nasalis muscle and their innervation

1. Transverse part

2. Alar part

Zygomatic Nerve (CN VII)

The posterior fibres of which muscle of mastication contribute to retrusion of the mandible?

Lateral pterygoid

A person can open the jaw only a small amount. At the temporomandibular joint, rotation of the mandibular head within the mandibular fossa still occurs normally. Which movement is restricted?

Anterior translation of the mandibular head

What are the main functions of the two parts of the nasalis muscle

Transverse part: narrows the nostrils

Alar part: flares nostrils

Name this muscle, innervation and main function

Name: Levator Labii Superioris Aleque Nasi

Innervation: Zygomatic Nerve

Function: Flares nostrils and raises the upper lip

Name this muscle, innervation, and function

Name: Orbicularis Oris

Innervation: Buccal Nerve

Function: Closes the mouth and protrudes the lipds (kissing or whistling)

What is the point of intersection for the orbicularis oris, risorius, and depresso anguli oris

Modiolus

Name the following six muscles of the upper lip

What are the muscles of the upper lips’ function and innervation

Dilators of the mouth

Innervated by: Zygomatic and Buccal nerve

What is the main funciton of the Risorius

Retracts corner of mouth

What is the main function of the levator anguli oris

Raises corner of the mouth

What is the main function of the levator labii superioris

Pull upper lip upwards

What is the main function of the Zygomaticus Minor + Major

Major = pulls corner of the mouht upward and laterally

Minor = ellevates upper lip

What is the main function of the Zygomaticus Major

Smiling

What are the muslces of the lower lip, their function, and what nerve their innervated by

Function: Dilators of mouth like upper lip muscles

Innervated by: Marginal Mandibular nerve (CN VII)

What is the function of the Depressor Anguli Oris and Depressor Labii I Inferioris

Pulls lower lip downward (sad and pout)

Identify this muscle, innervation, and function

Name: Mentalis

Innervated by: Marginal Mandibular Nerve (CN 7)

Function: Elevates and protrudes lower lip (pouting)

Identify this muscle, innervation, function

Name: Platysma

Innervation: cervical nerve (CN 7)

Function: Depresses mandible and draws corners down of mouth (grimacing or cringe emoji)

Identify this muscle, innervation, function

Name: Buccinator

Innervation: Buccal Nerve

Function: Presses cheek against teeth

What is the temporomandibular joint innervated by

CN V3 (Trigeminal V3)

What does the temporomandibular joint consist of and what are they separated by

Mandibular fossa

Articular tubercle

(Both are separated by the articular tubercle)

What is the function of the superior vs the inferior articular cavity of the temporomandibular joint

Superior articular cavity: allows mandible to glide (protrusion and retrusion)

Inferior articular cavity: allows hinge movements (elevation/closing and depression/opening and rotational movements of mouth)

Jaw is supported by LIGAMENTS, name the ligaments

• Joint Capsule

• 1 Intrinsic ligament (lateral ligament)

• 2 extrinsic ligament

  • Sphenomandibular

  • Stylomandibular

What are the muscles of massification innervated by

Trigeminal nerve

What are the muscles of massificaiton

• Temporalis

• Masseter

• Medial Pterygoid (2 heads)

• Lateral Pterygoid (2 heads)

Identify the upper muscle; innervation; and function

Name: Temporalis muscle

Innervated by: Trigeminal Nerve

Function: Elevates and retrudes mandible

Identify the inferior muscle; innervation, and funciton

Name: Masseter

Innervation: masseteric nerve (part of the trigeminal nerve)

Function: mainly elevates mandible and contribute to protrusion

Identify this muscle and its parts, innervation, function

Name: Medial Pterygoid

• Deep head and Superficial Head

Innervation: medial pterygoid nerve (part of trigeminal nerve)

Function: produce elevation and protrusion of mandible

Identify this muscle and its parts, innervaiton, and function

Name: Lateral Pterygoid

• Superior head and inferior head

Innovation:

• lateral pterygoid muscle (part of the trigeminal nerve)

Function:

• Bilaterally: depression and protrussion

• Unilateral: lateral or side to side chewing movements

Which masseter muscles are used in elevation movements

• Temporalis

• Masseter

• Medial Pterygoid

What masseter muscles are used for depression

Mainly gravity

Lateral pterygoid

Masseter broad attachment; direction of pull; main action

Attachment: Zygomatic arch → ramus of mandible

Direction of pull: Superiorly and postieriorly

Main actions: Elevates mandible (closes jaw)

Temporalis broad attachment; direction of pull; main action

Attachment: temporal fossa → coronoid process of mandible

Direction of pull: Superiorly & Posteriorly

Main action: Elevates and retracts mandible

Medial pterygoid broad attachment; direciton of pull; main action

Attachment: pterygoid region → medial surface of mandibular ramus / angle

Direction of pull: Superiorly & Posteriorly

Main action: Elevates and protracts mandible; assists side of side movement

Lateral Pterygoid broad attachment; direction of pull; main action

Attachment: sphenoid / pterygoid region - mandibular neck + TMJ disc / capsule

Which muscle is responsible for raising the upper eyelid and what nerve innervate it

Levator Palpebrae superioris

• CN 7

What muscle draws the eybrows together and downward? And what CN innervates this muscle

Corrugator supercilli

• CN 7

What muscle raises the eyebrows together and what CN innervates this muscle

Occipitofrontalis (frontal belly)

• CN 7

What muscles raise the corners of the mouth and what CN innervates it

Levator anguli oris and zygomaticus major

• CN 7

What muscle closes and purse the lips and wha CN innervates it

Obicularis Oris

• CN 7

What muscles lower the cortners of the mouth and what CN innervates it

Depressor anguli oris and platysma

• CN 7

What muscle presses the cheek against the teeth and what CN innervates it

Buccinator

• CN 7

Masseter;

origin and attachment;

direction of pull;

main action;

Motor supply: CN V3

Origin: zygomati arch

Insertion: ramus portion of mandibular

Direction of pull: superior

Main action: elevates mandible (closes jaw)

Motor supply: CN V3 (Trigeminal nerve)

Temporalis

origin and attachment;

direction of pull;

main action;

Motor supply: CN V3

Origin: temporal fossa

Insertion: coronoid process of the mandible

Direction of pull: superiorly & posteriorly

Main action: elevates and retracts (brings jaw back) mandible

Motor supply: CN V3

Medial Pterygoid:

origin and attachment;

direction of pull;

main action;

Motor supply:

Origin: pterygoing region

Insertion: Medial surface of ramus of mandibular

Direction of pull: Superiorly & Posteriorly

Main action: Elevates and protracts mandible (assists in side to side movement)

Motor Supply: CN V3

Lateral Pterygoid:

origin and attachment;

direction of pull;

main action;

Motor supply:

Origin: sphenoid/pterygoid region

Insertion: mandibular neck + TMJ disc / capsule

Direction of pull: Anterior

Main action: protracts mandible; assists jaw opening and side to side movement

Motor supply: CN V3