ENT Oral Anatomy

Question 1

What is the Oral Cavity Proper and the Oral Vestibule?

Answer 1

Oral Cavity Proper = Everything Above the Tongue and Below the Palate i.e. The Space in-between.

Oral Vestibule = Region located between the Posterior Aspect of the Lips and Anterior Aspect of the Teeth

Question 2

What muscles form the floor of the mouth i.e. the Muscular Diaphragm?

Answer 2

Mylohyoid (innervated by CN V3)

Geniohyoid (innervated by C1)

Question 3

Which gland creates a gap in the mouth that can result in infection tracking or tumour spread?

Answer 3

Submandibular Gland

Question 4

What are the 3 Major Salivary Glands?

Answer 4

1. Parotid Glands
2. Submandibular Glands
3. Sublingual Glands

Question 5

What is the function and innervation of the minor salivary glands?

Answer 5

Release basal secretions to keep mouth moist

Parasympathetic innervation via CN VII

Question 6

Where are the Salivary Gland secretions released?

Answer 6

Parotid Gland > Parotid Duct > Upper 2nd Molars

Submandibular Gland > Submandibular Duct > Lingual Caruncle.

The Sublingual Gland > Several Ducts, located Superiorly.

Question 7

What are the nerve innervations of the Salivary Glands?

Answer 7

Chorda Tympani > Sublingual and Submandibular Glands

CN IX > Parotid Glands

Question 8

What is the nerve innervation for the Anterior (Horizontal) 2/3 of the Tongue?

Answer 8

General Sensory Innervation from CN V3

Special Sensory (Taste) Innervation from CN VII

Question 9

What is the nerve innervation for the Posterior (Vertical) 1/3 of the Tongue?

Answer 9

General Sensory and Special Sensory (Taste) Innervation from CN IX

Question 10

Papillae are taste buds. True/False?

Answer 10

FALSE.

Papillae contain taste buds or sensory cells.

Question 11

Which taste buds sense taste?

Answer 11

Fungiform
Vallate
Foliate

NOT FUSIFORM
Senses touch, temperature and pain

Question 12

Which tongue muscle is NOT innervated by CN XII?

Answer 12

Palatoglossus, innervated by CN X

Question 13

Through which foramen does CN XII exit the cranium?

Answer 13

Hypoglossal Canal

Question 14

How do you test the CN XII?

Answer 14

Ask the Patient to Stick their Tongue Out.

If BOTH CN XII’s are Functional, the Tongue Tip remains in the MIDLINE upon Protrusion

In Unilateral CN XII Damage, the Tongue Tip will POINT TOWARDS the Side of the Injured Nerve as the CN XII PUSHES the Tongue Out and so, will cause the Tongue to Deviate to the Injured Side

Question 15

What is the blood supply to the tongue?

Answer 15

Lingual Arteries, which branch off the External Carotid Artery

Question 16

What is the difference in the routes between the tongue innervating arteries and nerves?

Answer 16

The Arteries pass MEDIAL to the Hyoglossus Muscle

The Nerves pass LATERAL to the Hyoglossus Muscle

Question 17

What are the folds of the hard palate called?

Answer 17

Rugae

Reduce friction against food in mouth

Question 18

What are the Bilateral Muscles of the Soft Palate of the Mouth?

Answer 18

Tensor Veli Palatini 
Palatopharyngeus 
Palatoglossus
Levator Veli Palatini 
Musculus Uvulae

Question 19

What is the main innervation for the Bilateral Muscles of the Soft Palate of the Mouth?

Answer 19

CN X

Except Tensor Veli Palatini, which is innervated by CN V3

Question 20

How do you clinically test CN X?

Answer 20

Here, ask the Patient to say “Ahhhhhh” which will cause the CN X to Tense all the Muscles.

If the CN X Nerves are Functioning Normally, the Uvula should Lift Straight Up in the MIDLINE

If there is Unilateral CN X Nerve Pathology, the Uvula will be Pulled AWAY FROM the Non-Functioning Side by the Normal Side, pulling the Tongue AWAY from the Side of Dysfunction.

Question 21

What are the muscles of the outer circular layer of the Pharynx?

Answer 21

Superior Constrictor Muscle
Middle Constrictor Muscle
Inferior Constrictor Muscle

Act to Push the Food Bolus Inferiorly towards the Oesophagus

Question 22

What are the muscles of the inner longitudinal layer of the Pharynx?

Answer 22

Stylopharyngeus
Palatopharyngeus
Salpingopharyngeus

Act to pull the larynx superiorly to shorten pharynx during swallowing

Question 23

What is the main innervation to the pharyngeal muscles?

Answer 23

CN X

Except for Stylopharyngeus which is CN IX

Question 24

What is Waldeyer’s Ring?

Answer 24

Ringed Arrangement of Lymphoid Tissue that lies Within the Mucosa of the Nasopharynx and Oropharynx.

Consists of Pharyngeal (Adenoid) Tonsils, Tubal Tonsils, Palatine Tonsils and Lingual Tonsils