Zill - Oral Cavity

Question 1

Muscle: Digastric

Action:

Innervation:

Answer 1

Muscle: Digastric

Action: Open Mouth

Innervation: V3, VII

Question 2

Muscle: Mylohyoid

Action:

Innervation:

Answer 2

Muscle: Mylohyoid

Action: Raise floor of mouth

Innervation: V3

Question 3

Muscle: Geniohyoid

Action:

Innervation:

Answer 3

Muscle: Geniohyoid

Action: Pull hyoid forward

Innervation: C1 (w/ XII)

Question 4

Order of Genioglossus, Geniohyoid, Mylohyoid on bisected head?

Answer 4

Genioglossus = Tongue fibers perpendicular to rest

Geniohyoid - Mylohyoid - Digastric ant. belly from top to bottom

Question 5

Clinical: Ludwig’s Angina

Answer 5

Infection of floor of mouth (submandibular space) often due to spread from adscessed mandibular tooth

Obstruction can push up tongue and obstruct airway

Question 6

Sensory Breakdown of Tongue

Answer 6

Sulcus Terminalis (V shape) divides

Ant 2/3 = Oral = Somatic Sensory and Taste

Post 1/3 = Pharyngeal = Visceral Sensory and Taste

Ant. to Epiglottis - CN X, Visceral Touch and Taste

Post 1/3 - CN IX

Ant 2/3 - V3 (Som. Sensory), CN VII (Taste)

Question 7

What are the openings of the Submandibular Salivary Glands?

Answer 7

Sublingual Papilla - swellings at base of frenulum

Question 8

Muscle: Genioglossus

Action:

Innervation:

Answer 8

Muscle: Genioglossus

Action: Protrude Tongue

Innervation: XII

Question 9

Muscle: Styloglossus

Action:

Innervation:

Answer 9

Muscle: Styloglossus

Action: Draws tongue superiorly and posteriorly

Innervation: XII

Question 10

Muscle: Hyoglossus

Action:

Innervation:

Answer 10

Muscle: Hyoglossus

Action: Depress tongue

Innervation: XII

Question 11

Clinical: Sign of Damage to Hypoglossal Nerve (XII)

LMN?

UMN?

Answer 11

Genioglossus Paralyzed

Lower Motor Neuron lesion

Protruded tongue deviates toward LMN lesion due to unopposed action of the Genioglossus

UMN - Tongue deviates away from side of cortical lesion

(Saying same thing, just takes into account desuccation of motor neuron)

Question 12

What is a clinical result of the lymph pathway in the tongue?

Answer 12

Lymphatics cross midline, infection may spread to opposite side (cancer, disease, etc)

Question 13

Muscle: Palatoglossues

Action:

Innervation:

Answer 13

Muscle: Palatoglossues

Action: Draws palate down, raise tongue

Innervation: CN X

Question 14

Chorda Tympany (VII)

Answer 14

Hitch hikes on V3 (Lingual Nerve)

Parasympathetics to submandibular, sublingual salivary glands

Taste fibers to Ant 2/3 tonge

Question 15

Clinical: What nerve is often damaged in mouth during dental extraction or children fall w/pop bottle in mouth?

Answer 15

Lingual Nerve

Lose touch and taste

1) V3 - General Sensation to Ant. Tongue
2) CN VII (hitch hiking) Taste to Ant. Tongue

Question 16

Clinical: Damage to Facial Nerve @ Int. Auditory Meatus

vs

Clinical: Damage to Facial Nerve @ Stylomastoid foramen or Parotid Gland

Answer 16

CN VII and CN VIII

Auditory/Vestibular defects

All facial nerve symptoms

CN VII

Only facial paralysis!

No TASTE, No hyperacousia, No decreas in secretion of lacrimal/salivery glands