Oral Cavity

Question 1

What is the innervation of of these muscles found in the floor of the mouth?

Answer 1

The mylohyoid (n. to the mylohyoid); geniohyoid (C1 via XII).

Question 2

Where is the location of duct openings for all three salivary glands?

Answer 2

Parotid: external to the 2nd upper molar;
Submandibular: submandibular papilla on floor of mouth;
Sublingual: 15-20 openings along sublingual fold on lateral aspects of base of tongue.

Question 3

List the four types of lingual papilla.

Answer 3

Filiform, fungiform, foliate, aand circumvallate.

Question 4

Which lingual papillae exhibit taste buds?

Answer 4

The circumvallate and fungiform papillae.

Question 5

Which lingual papillae may keratinize?

Answer 5

The filiform and fungiform (slight) papillae.

Question 6

What does the foramen cecum represent?

Answer 6

The site of invagination of epithelium that formed the thyroid gland.

Question 7

Where is the foramen cecum found?

Answer 7

It is located at the apex of the sulcus terminalis on dorsum of the tongue.

Question 8

What is the thyroglossal duct?

Answer 8

The pathway of descent for the thyroid duct into the neck from the foramen cecum.

Question 9

To what four things is the tongue anchored?

Answer 9

Styloid process, hyoid bone, mandible, pharynx

Question 10

List the muscles of the floor of the mouth from superficial to deep.

Answer 10

The mylohyoid and the geniohyoid mm.

Question 11

Lymphatic drainage of tongue

Answer 11

Tip: submental nodes

Anterior 2/3: submandibular and deep cervical

Posterior 2/3: deep cervical

Question 12

List the extrinsic muscles of the tongue and their innervation and function

Answer 12

1) genioglossus: protrude tongue, depress medial region
2) hyoglossus: depressor and retractor of tongue
3) styloglossus: retract tongue
4) palatoglossus: constricts orophayngeal isthmus, elevates root of tongue

all innervated by XII except the palatoglossus which is XI via X (pharyngeal plexus).

Question 13

What nerve supplies sensation and taste to the epiglottis?

Answer 13

Vagus

Question 14

What supplies sensory innervation to the palate? motor??

Answer 14

greater and lesser palatine nn (V2) sensory

Motor: XI via X… Except tensor palati (V3)

Question 15

What is the bony composition of the hard palate?

Answer 15

The anterior 2/3 = maxilla, the posterior 1/3 = palatine.

Question 16

Which muscles comprise the soft palate?

Answer 16

The palatoglossus, palatopharyngeus, musculus uvulus, levator palati, and tensor palati.

Question 17

Into what do the muscles of the soft palate insert?

Answer 17

The palatine aponeurosis.

Question 18

What is the action/innervation of each of the muscles of the soft palate?

Answer 18

The palatoglossus: pulls lateral aspects of tongue up;

Palatopharyngeus: adducts posterior pillars and pulls pharynx up;

Musculus uvulus: elevates and contracts uvula;

Levator palati: KEY mover of soft palate - elevates;

Tensor palati: tenses palate.

ALL innervated by XI via X (pharyngeal plexus) except tensor palati (V3).

Question 19

What are the 3 divisions of the pharynx and the communications (things that open into) in each region?

Answer 19

Nasopharynx (posterior choanae of nasal cavity);

Oropharynx (oral cavity through the posterior arch);

Laryngopharynx (larynx).

Question 20

What is the innervation and function of the pharyngeal constrictors?

Answer 20

The pharyngeal constrictors constrict the pharynx and force contents downward. They are innervated by XI via X (pharyngeal plexus).

Question 21

What muscle separates superior and middle constrictor? Innervation?

Answer 21

Stylopharyngeus m, CN IX

Question 22

How is the nasal septum constructed?

Answer 22

By the perpendicular plate of ethmoid, vomer, and septal cartilage.

Question 23

Be able to label a diagram of the lateral wall of the nasal cavity that illustrates the various meatuses and the non-sinus structures that open into each.

Answer 23

This is important (top of page 380). It is generally asked in matching question: inferior meatus: nasolacrimal duct; middle meatus: frontal sinus, maxillary sinus, ant & middle ethmoidal air cells; superior meatus: posterior ethmoidal air cells; sphenoethmoidal recess: sphenoidal sinus.

Question 24

List the four paranasal air sinuses and their specific site of drainage into the nasal cavity (meatuses).

Answer 24

Frontal sinus: hiatus semilunaris of middle meatus;

Maxillary sinus: hiatus semilunaris of middle meatus;

Ethmoidal air cells (anterior) hiatus semilunaris; (middle) bulla ethmoidalis of middle meatus; (posterior) superior meatus;

Sphenoid sinus: sphenoethmoidal recess.

Question 25

Where is the olfactory epithelium located?

Answer 25

On the roof of nasal cavity and extending for a short distance down medial septum and surface of the superior concha.

Question 26

What are filia olfactoria?

Answer 26

The axons of the olfactory epithelium.

Question 27

What is the function of the cribriform plate of the ethmoid bone?

Answer 27

To allow filia olfactoria of the olfactory epithelium to pass superiorly into cranial cavity (bulb).

Question 28

Where do the olfactory axons first synapse?

Answer 28

In the olfactory bulb that lies on top of each cribriform plate.

Question 29

What is the major innervation and arterial supply to the lateral wall of the nasal cavity.

Answer 29

The maxillary division of the trigeminal (innervation of posterior and nostril) mandible division of V (anterior superior) and the sphenopalatine a. (blood supply).

Question 30

Name the cartilages that form the larynx and epiglottis?

Answer 30

Epiglottis, thyroid, cricoid, and arytenoid.

Question 30

What type of cartilage forms the larynx? the epiglottis? Why?

Answer 30

They are all hyaline except epiglottis which is elastic cartilage. The epiglottis folds down to allow food/water to pass over opening of larynx EACH time you swallow so must be able to “spring” back. Elastic cartilage is highly resilient.

Question 31

List the primary extrinsic and intrinsic laryngeal muscles, their function and
innervation.

Answer 31

Extrinsic: sternothyroid (ansa) and thyrohyoid (C1 via XII);

Intrinsic: all supplied by recurrent laryngeal nn. except for cricothyroid (external laryngeal n.); all intrinsic are adductors of the vocal folds except the posterior cricoarytenoid which is the sole abductor.

Question 32

What is the pattern of sensory innervation of the larynx?

Answer 32

The mucosa down to the superior surface of the vocal folds via internal laryngeal n.; the mucosa from there down from the recurrent laryngeal nn.

Question 33

Know the various rules of exception, regarding muscle innervation, for the head/neck.

Answer 33

Summarized just after the cranial nn. section (page 367). These are important!