anatomy comp 3

The posterior belly of digastric is innervated by

Facial nerve (CN VII)

Innervation of medial pterygoid

Medial pterygoid nerve (CN V3)

Innervation of lateral pterygoid

Lateral pterygoid nerve (CN V3)

Nerve for general sensation to anterior 2/3 tongue

Lingual nerve (CN V3)

Innervation of levator anguli oris

Facial nerve (CN VII) — buccal branch

Innervation of orbicularis oculi

Facial nerve (CN VII) — temporal & zygomatic branches

Innervation of zygomaticus major

Facial nerve (CN VII) — buccal branch

Innervation of levator labii superioris

Facial nerve (CN VII) — buccal branch

Innervation of levator anguli oris

Facial nerve (CN VII) — buccal branch

Innervation of orbicularis oris

Facial nerve (CN VII) — buccal branch

Innervation of buccinator

Facial nerve (CN VII) — buccal branch

What are the five layers of the scalp

• Skin

• Connective tissue (dense, bleeds a LOT)

• Aponeurosis (epicranial aponeurosis)

• Loose connective tissue (danger space — infection spread)

• Pericranium

pupil control is by

CN 3

Superior orbital fissure contents

CN III, IV, V1, VI + superior ophthalmic vein

Foramen rotundum contents

CN V2

Foramen rotundum contents

CN V2

Middle meningeal artery entry

Foramen spinosum

CN V3 exit

Foramen ovale

Facial nerve exit skull to face

Stylomastoid foramen

Jugular foramen contents

CN IX, X, XI + internal jugular vein

Down-and-out eye, ptosis, dilated pupil

CN III palsy

Inability to look down & in

CN IV palsy (superior oblique)

Medial deviation of eye

CN VI palsy (lateral rectus)

The tensor tympani is controlled by

CN V3

The lateral pterygoid action

Protracts and opens mandible

Taste is innervated by

CN 7 (chords tympanii)

Nerve to mylohyoid innervates?

Mylohyoid + anterior belly of digastric (branch of inferior alveolar nerve, V3)

What innervates muscles of mastication?

Mandibular division of trigeminal nerve (CN V3)

• Masseter

• Temporalis

• Medial pterygoid

• Lateral pterygoid

Buccal branch of facial nerve innervates?

Buccinator, upper lip muscles (levator labii superioris, levator anguli oris, orbicularis oris)

Mandibular branch of facial nerve innervates?

Depressor anguli oris, depressor labii inferioris

Terminal branch of inferior alveolar artery

Mental artery → chin & lower lip

What does the superior labial artery supply?

Upper lip & nasal septum

Facial artery → key terminal region

Becomes angular artery at medial angle of eye

Hinge (depression/elevation) =

inferior compartment of the tmj

The temporal is is innervated by the

CN V3

Action of the frontalis (frontal belly)

Elevates eyebrows and wrinkles forehead

Action of the orbicuoaris oculi

Closes eyelids

Action of the zygomaticus major

Elevates angle of the mouth to smile

The stylohyoid is innervated by

The facial nerve (CN VII)

Sternohyoid innervation is by

Ansa cervicalis

The omohyoid is innervated by

Ansa cervicalis

The sternothyroid is innervated by

Ansa cervicalis

Intrinsic laryngeal muscles (except cricothyroid) innervation

Recurrent laryngeal nerve (CN X)

SCM unilateral actions

ipsilateral head tilt, contralateral rotation

Bilateral activation of the SCM causes

Neck flexion and assists in inhalation

Sternohyoid action

Depresses hyoid after swallowing

Omohyoid action

Depresses and retracts the hyoid

The sternothyroid action

Depresses thyroid cartilage (larynx)

Anterior Scalene — action

Elevates 1st rib; flexes neck

Middle Scalene — action

Elevates 1st rib; lateral neck flexion

Posterior Scalene — action

Elevates 2nd rib; lateral neck flexion

Cricothyroid — action

Tenses & elongates vocal cords (increases pitch)

Mylohyoid — action

Elevates hyoid & floor of mouth; aids in swallowing

Stylohyoid — action

Elevates & retracts hyoid (swallowing)

Digastric (both bellies) — action

Depresses mandible; elevates hyoid during swallowing