Lecture 12: Oral and Nasal Cavities, Pharynx & Pterygopalatine Fossa

Question 1

What is the major arterial supply to the posterior 2/3 of the nasal cavity?

Answer 1

• Sphenopalatine artery, through its 2 major branches:
  1) Posterior Lateral Nasal artery
  2) Posterior Septal artery

Question 2

Label this

Answer 2

Question 3

The parotid duct pierces what muscle and drains into the mouth where?

Answer 3

• Pierces the Buccinator M.
• Drains into mouth opposite the crown of the 2nd upper molar

Question 4

Which nerve is the Submandibular duct in close relationship to?

Answer 4

• The lingual nerve spirals around the submandibular duct from superior-lateral to inferior-medial
• Looking in floor out mouth the duct sits on top of the nerve

Question 5

What is the dental formula for adults and how does it work?

Answer 5

In each set, incisors (I) are indicated first, canines (C) second, premolars (P) third, and finally molars (M), giving I:C:P:M.

• Formula 2-1-2-3 for upper teeth indicates 2 incisors, 1 canine, 2 premolars, and 3 molars on one side of the upper mouth

Question 6

What is the dental formula for children’s (decidous) teeth?

Answer 6

• 2-1-0-2

- 2 incisors, 1 canine, 0 pre-molars, 2 molars on each side of the top and bottom

Question 7

What provides the GSA and SVA fibers to the anterior 2/3 of tongue; and what is each of the nerves responsible for?

Answer 7

• Lingual nerve from Trigeminal (V): supplies the GSA fibers for pain, temp., touch
• Chorda Tympani from Facial (VII) supplies the SVA fibers for taste

*Chorda Tympani from Facial n. travels with the Lingual n. to the tongue

Question 8

What supplies the GVA and SVA fibers to the posterior 1/3 of tongue?

Answer 8

Glossopharyngeal (IX) is responsible for both the GVA and SVA (taste) fibers.

Question 9

The tonsillar fossa region of the tongue is innervated by what nerve?

Answer 9

• Glossopharyngeal (IX) nerve
• Arises from endoderm of 2nd pharyngeal arch

Question 10

All the extrinsic and intrinsic muscles of the tongue are innervated by; what is the one exception and its innervation?

Answer 10

• ALL tongue muscles = hypoglossal (CN XII)
• Except! Palatoglossus is innervated by CN X

Question 11

Unilateral hypoglossal palsy results in what; which way does tongue deviate and why?

Answer 11

• Paralysis, atrophy, and fasciculations of the intrinsic muscles of tongue
• When protruded, the normal genioglossus deviates the tongue toward the affected side!

*BILATERAL paralysis may cause airway obstruction (dyspnea), dysarthria, and dysphagia

Question 12

The tongue is supplied by which artery and branch?

Answer 12

Lingual artery and its terminal branch, the profunda lingual artery

Question 13

Which vein drains the tongue and into where?

Answer 13

Lingual vein drans into IJV or facial vein

Question 14

Lymphatics from the tongue primarily drain to where?

Answer 14

• Deep Cervical LN’s:
  1) Jugulodigastric
  2) Jugulo-omohyoid

Question 15

What is the innervation and action of Tensor Veli Palatini muscle?

Answer 15

• Innervated by small branch of Mandibular n. (V3)
• Tense the palate and opens the auditory tube (depressurizes middle ear)

Question 16

What is the innervation and action of Levator Veli Palatini muscle?

Answer 16

• Innervated by CN X, pharyngeal plexus
• Elevates the soft palate

Question 17

Paralysis of the Tensor Veli Palatini or Levator Veli Palatini muscles will lead to?

Answer 17

Muscles of the non-paralyzed side will pull or deviate the uvula TOWARD the normal side

Question 18

What is the blood supply and innervation like to the palate, including hard and soft palate?

Answer 18

• Greater palatine nerve and artery supply hard palate
• Lesser palatine nerve and artery supply soft palate

- Nasopalatine nerve supplies anterior 1/3 of hard palate

*The greater and lesser palatine arteries are branches off the descending palatine artery, which is one of the last branches off the Maxillary artery!

Question 19

Which ganglion do the nerves supplying the palate arise from; and which nerve is the main one innervating the palate?

Answer 19

• Sensory nerves of the palate are branches of the Maxillary nerve (V2), which branch from the:
• Sphenopalatine Ganglion

Question 20

What muscles are critical for closing off the pharyngeal isthmus and separating the nasopharynx from the oropharynx?

Answer 20

Levator Veli Palatini and Tensor Veli Palatini

Question 21

The pharyngeal plexus innervating the pharynx receives what type of fibers from which nerves?

Answer 21

• GVA fibers from the pharyngeal branch of glossopharyngeal n. (IX)

- SVE fibers from the pharyngeal branch of vagus n. (X)

Question 22

What is the 2 main sources of blood supply to the palatine tonsil?

Answer 22

1) Tonsilar artery of the Facial a.
2) Palatine branch of the Ascending Pharyngeal a.

Question 23

What nerve is closely related to the floor of the tonsilar fossa?

Answer 23

Glossopharyngeal nerve

*He mentioned surgeons bagging this nerve by accident when removing the tonsils

Question 24

Lymphatic drainage of the tonsils is to where?

Answer 24

Directly into the Jugulodigastric (tonsilar) Nodes - Deep Cervical Nodes

Question 25

Fractures of the nose frequently occur at what junction?

Answer 25

Junction between the **septal cartilage** and the **ethmoid and vomer**

Question 26

Where is the Sphenoethmoidal Recess and why is it relevant?

Answer 26

- Postero-superior to superior concha - **Sphenoidal sinus** drians into the sphenoethmoidal recess

Question 27

What important structures/openings found in the Superior Concha and Meatus?

Answer 27

- Openings for the posterior ethmoial air cells - Sphenopalaine Foramen

Question 28

What important structures and openings found in the Middle Meatus?

Answer 28

- Ethmoidal bulla - Hiatus Semiluniaris - Openings for the: **Maxillary, Ethmoidal and Frontal Sinuses**

Question 29

The opening for the maxillary sinus is located where?

Answer 29

- Posterior 1/3 of the **hiatus semilunaris**

Question 30

The frontal and anterior ethmoidal sinuses drain into the \_\_\_\_\_\_, which is located in the anterosuperior portion of the \_\_\_\_\_\_\_\_\_.

Answer 30

- Drain into the **ethmoidal infundibulum** - **Hiatus semilunaris**

Question 31

What are the 2 openings for the frontal sinus?

Answer 31

1) Ethmoidal infundibulum 2) Frontal Recess

Question 32

Where is the opening for the nasolacrimal duct?

Answer 32

Inferior meatus

Question 33

What is the blood supply for the posterior 2/3 of the nasal cavity and what supplies the anterior 1/3?

Answer 33

**Posterior 2/3:** the **sphenopalatine artery** with the posterior lateral and posterior septal branches **Anterior 1/3:** the **anterior and posterior ethmoidal as.** branches of the opthalmic artery

Question 34

Most nasal hemorrhages or (**epitaxis**) occurs at the junction of what?

Answer 34

- Septal branches of the **superior labial** and **sphenopalatine arteries** - Clinically this region is referred to as: **Kiesselbach's area**

Question 35

Most of the lymphatic drainage of the nose is to which nodes?

Answer 35

Jugulodigastric (deep cervical nodes)

Question 36

Where are the Olfactory neurons found in the nasal cavity and what type of fibers are they?

Answer 36

- Embedded in the **olfactory epithelium** ## Footnote **- SVA fibers**

Question 37

What supplies the innervation to the posterior 2/3 and anterior 1/3 of nasal cavity?

Answer 37

**Posterior 2/3:** branches of the **sphenopalatine (pterygopalatine) ganglion** **Anterior 1/3:** the **anterior ethmoidal nerve**, a branch of the nasociliary nerve (**V1**)

Question 38

Which nerve innervates the mucosa of the gingiva and hard palate adjacent the upper incisors?

Answer 38

- Nasopalatine nerve, a branch of the sphenopalatine (pterygopalatine) ganglion

Question 39

What is the Salpingopharyngeal Fold and what muscle forms it?

Answer 39

- Mucosal fold that extends between the posterior part of the torus and pharyngeal wall - Formed by the underlying **salpingopharyngeus muscle.**

Question 40

Which fossa does the sphenopalatine ganglion lie in and where is it found anatomically?

Answer 40

- Within the **Sphenopalatine fossa** which is located **posterior** to the **maxillary sinus**, - Between the **pterygoid portion of the sphenoid bone** and the **palatine bone**

Question 41

What neurovasculature is found within the sphenopalatine fossa?

Answer 41

- Short Maxillary nerve (**V2**) enters via **foramen rotundum** and exits via the **inferior orbital fissure** - Sphenopalatine artery the **terminal branch** of the Maxillary artery

Question 42

What are the branches of the Pterygopalatine Ganglion?

Answer 42

1. **Vidian nerve** formed by merging of **deep petrosal** and **great petrosal nerves** 2. **Lesser and Greater Palatine nerves** 3. **Nasopalatine nerve**

Question 43

What does the roof of the Maxillary Sinus form; why is this clinically significant, what's found here?

Answer 43

- Forms the **floor of the orbit** - Floor of the orbit is where the **infraorbital nerve** lies in the **infraorbital canal** - Blows to the eyeball can herniate orbital contents into maxillary sinus and entrap the maxillary nerve: will have **numbness in the cheek of affected side**

Question 44

What are the relationships of the sphenoidal sinus, posterior, superior, anterior, inferior, and lateral? (\*He really stressed this!)

Answer 44

Posterior: pons and basilar artery **SUPERIOR:** **PITUITARY GLAND!** Anterior: nasal cavity Inferior: nasopharynx **LATERAL: INTERNAL CAROTID, V1, CAVERNOUS SINUS**

Question 45

Which sinus is frequently used as a surgical approach to its surrounding structures?

Answer 45

- Maxillary sinus - Transmaxillary approach!