Mod 4: Lecture 4 - Nasal and Oral Cavities

Question 1

Above and Below the nasal cavity

Answer 1

• Above the nasal cavity: anterior cranial fossa
• — perforated cribriform plate of the ethmoid bone
• Below the nasal cavity: oral cavity
• — hard palate forms a common partition separating the oral cavity below from the nasal cavity above

Question 2

Lateral to the Nasal cavity

Answer 2

• Lateral to the upper half of the lateral wall of the nasal cavity: ethmoidal air sinus
• — lateral to the sinus is the medial wall of the orbit
• Lateral to the lower half of the lateral wall is the maxillary air sinus

Question 3

Posterior to the nasal cavity

Answer 3

• continuous posteriorly with the nasopharynx

- – where the post nasal drip goes

Question 4

Roof of the nasal cavity

Answer 4

• nasal cartilages
• — seen best in anterior view
• nasal bones
• nasal spine of the frontal bone
• cribriform plate of the ethmoid bone
• anterior and inferior aspects of the body of the sphenoid bone

Question 5

Floor of the nasal cavity

Answer 5

• palatine processes of the maxilla

- horizontal plates of the palatine bone

Question 6

Medial Wall of the nasal cavity

Answer 6

• formed by the nasal septum
• — separates the nose into two nostrils
• components of the nasal septum:
• — septal cartilage: why you can break your nose and it’s no big deal
• — perpendicular (vertical) plate of ethmoid bone
• vomer

Question 7

Lateral Wall of the Nasal cavity

Answer 7

• skeletal components:
• — maxilla
• — ethmoid bone: which provides the superior and middle conchae
• — inferior conchae
• other contributors:
• — medial pterygoid plate of the sphenoid bone
• — nasal bone
• — lacrimal bone
• — palatine bone

Question 8

Nasal Conchae

Answer 8

• superior, middle, and inferior conchae
• divide the nasal cavity into four passages
• — sphenoethmoidal recess: above the superior conchae
• — superior meatus: between the superior and middle conchae
• — middle meatus: between the middle and inferior conchae
• — inferior meatus: below the inferior conchae

Question 9

Clinical Correlation: Nasogastric (NG) tube

Answer 9

• the nasal cavity is continuous with the nasopharynx which is continuous with the esophagus
• NG tube is passed from the nasal cavity to the stomach

Question 10

Paranasal Sinuses

Answer 10

• air filled extensions of the respiratory part of the nasal cavity
• — sinus pain under the eyes
• — look like honeycomb in the bones
• go into the following cranial bones:
• — frontal
• — ethmoid
• — sphenoid
• — maxilla

Question 11

Frontal Sinuses

Answer 11

• between the outer and inner tables of the frontal bone
• posterior to the superciliary arches and the root of the nose
• directly above the bridge of the nose
• — sinus pain between the eyes
• the most anterior of the paranasal sinuses

Question 12

Ethmoidal Air Cells

Answer 12

• all the little honeycomb parts of the paranasal sinuses that are posterior to the frontal sinus
• small invaginations of the middle and superior nasal meatus into the ethmoid bone

Question 13

Sphenoidal Sinuses

Answer 13

• located in the body of the sphenoid and may extend into the wings of this bone
• unevenly divided and separated by a bony septum
• posterior to the honeycomb sinuses
• — the most posterior of the paranasal sinuses
• near the ear - why your ears hurt when you have sinus infections

Question 14

Maxillary Sinuses

Answer 14

• largest of the paranasal sinuses
• occupy bodies of the maxillae
• communicate with the middle nasal meatus
• medial wall of the maxillary sinus forms the inferior part of the lateral wall of the nasal cavity
• roof of the maxillary sinus is formed by the floor of the orbit
• — why you feel like your eyes are going to pop out of your head
• floor of the maxillary sinus is formed by the alveolar part of the maxilla of the oral cavity
• — why your teeth hurt when you have a sinus infection

Question 15

Oral Regions

Answer 15

• Oral Vestibule
• Oral Cavity Proper: space between upper and lower dental arches
• — what you think of as the mouth

Question 16

Oral Vestibule

Answer 16

• space between teeth and mucosal lining of the lips and cheeks
• — labial and buccal mucosa
• — where the squirrel holds their nuts
• controlled by muscles of facial expression
• — these muscles are innervated by facial nerve (CN VII)
• — buccinator

Question 17

Buccinator

Answer 17

• thin, flat, rectangular muscle
• attaches laterally to the alveolar processes of the maxillae and mandible, opposite the molar teeth
• attaches to the pterygomandibular raphe
• — a tendinous thickening of the buccopharyngeal fascia (deep fascia of the neck)
• occupies a deeper more medially located plane than the other facial muscles
• — passing deep to the mandible so that it is more closely related to the buccal mucosa than skin of the face
• active in smiling, keeps the cheek taut
• — thereby preventing the cheek from folding and being injured during chewing

Question 18

Salivary Gland Associated with Oral Vestibule

Answer 18

• Parotid Gland
• — duct opens in the oral vestibule opposite the crown of the second molar
• — way in the back of the mouth, in between the cheek and teeth

Question 19

Palate

Answer 19

• forms the roof of the oral cavity proper and floor of nasal cavity
• two distinct parts:
• — hard palate
• — soft palate

Question 20

Hard palate

Answer 20

• forms rigid surface for food during chewing
• formed from 2 bones of skull
• — horizontal plate of palatine bone (posterior 1/3)
• — palatine process of maxilla (anterior 2/3)

Question 21

Soft Palate

Answer 21

• rises as a reflex to close off nasopharynx during swallowing
• — doesnt work when milk comes out your nose
• sides are attached to pharyngeal walls

Question 22

Tonsils

Answer 22

• aggregates of lymphoid tissue
• palatine: bilateral, located at boundary of oral cavity and pharynx
• pharyngeal: single, roof of nasal pharynx
• lingual: dorsal surface of posterior tongue

Question 23

Tongue

Answer 23

• Functions:
• — mastication
• —- taste
• —- deglutition (swallowing)
• — articulation (speech)
• — oral cleansing
• has a dorsal and ventral (sublingual) surface
• composed of intrinsic and extrinsic muscles

Question 24

Dorsal Surface of the Tongue

Answer 24

• Sulcus Terminalis
• Circumvallate Papillae
• Filiform and Fungiform Papillae

Question 25

Sulcus Terminalis

Answer 25

• dorsal surface of tongue
• v shaped groove that divides anterior 2/3 from the posterior 1/3 of tongue
• — behind the super bumpy part of tongue in the back of the mouth, too far back to feel

Question 26

Circumvallate Papillae

Answer 26

• dorsal surface of tongue
• 8-10 rows of structures containing taste buds
• super bumpy part of tongue in the back of the mouth

Question 27

Filiform and Fungiform Papillae

Answer 27

• dorsal surface of tongue
• projections on the surface of the tongue
• in the anterior 2/3 where you can easily see them
• fungiform papillae contain taste buds
• filiform papillae direct food

Question 28

Sublingual Surface of Tongue

Answer 28

• Lingual Frenulum
• — a midline fold of mucous membrane running from the lingual gingiva (gums) behind the mandibular central incisors (bottom front teeth)
• Sublingual Papilla and opening of submandibular duct
• — the bump at the bottom of the frenulum

Question 29

Floor of Mouth

Answer 29

• a muscular diaphragm

- two cord-like geniohyoid muscles

Question 30

Muscular Diaphragm on Floor of mouth

Answer 30

• fills the u-shaped gap between the sides and body of the mandible
• — the space where the underside of your chin is
• composed of paired mylohyoid muscles
• — attachments: mylohyoid line of mandible to median raphe of hyoid bone
• — innervation: nerve to mylohyoid from IAN

Question 31

Geniohyoid muscles on the floor of the mouth

Answer 31

• two, cord-like
• above the diaphragm
• run from the mandible to the hyoid
• attachments: inferior mental spines of mandible to body of hyoid bone
• innervation: C1
• strips in the center of the floor of the mouth

Question 32

Structures in the Floor of the Mouth

Answer 32

• Glands and Ducts: submandibular duct and sublingual gland
• Lingual Nerve: sensory, anterior 2/3 of tongue
• hypoglossal nerve: motor, to intrinsic and extrinsic muscles of tongue