Nasal and Oral Cavity Flashcards
What is the piriform aperture formed by?
the right and left maxilla inferiorly and the two small nasal bones superiorly
What divides the nasal cavity into right and left sides?
a midline bony (perpendicular plate of the ethmoid and the vomer) and cartilaginous nasal septum
What structure of the nasal cavity contains a large amount of hairs to help filter inhaled air?
the nasal vestibule
Immediately posterior to the nasal vestibules is what?
the three nasal conchae, superior, middle, and inferior
The three nasal conchae divide the lateral spaces of the nasal cavity into what?
a series of groove-like passageways, the meatuses
The superior and middle concha are part of which bone?
the ethmoid bone. The inferior concha is a separate bone (the inferior turbinate)
Are the meatus’ below or above their associated concha?
below
Above the superior concha is a space called?
the sphenoethmoidal recess
What are some of the functions of the mucosa of the nasal cavity?
they help to filter inhaled air by trapping particles in the mucus, and the epithelial cells bear cilia that sweep the secretions toward points where the mucus can be eliminated (either by blowing your nose or sniffing hard enough that the secretions end up in the pharynx and are swallowed). They also help warm the air via increased surface area created by the concha
Hairs in the vestibule and mucus that is produced by goblet cells or secreted by glands trap particles larger than?
> 10 um
Some of the large particles are also trapped by what?
cells of the palatine and pharyngeal tonsils. By the time air reaches the trachea, most of the larger particles have been filtered out. The trachea then removes most particles from the 2-10 um size range
Particles trapped in the trachea are removed via what processes?
coughing and mucokinesis
Particles less than 2 um are removed where? By what mechanism?
in the lungs via phagocytosis by alveolar macrophages (dust cells)
NOTE: since alveolar membranes are very thing, they could dry out with not for the humidification that takes place in the airway spaces down through the bronchi
T or F. There is no mucus in health alveoli and there are ciliated cells
F. There are neither
The floor of the nasal cavity is made up of what bones? aka the hard palate
the palatine process of the maxilla (anterior 3/4) and the horizontal process of the palatine bone (posterior 1/4)
Where does the soft palate attach to the floor of the nasal cavity?
in the posterior region and hangs down posterior to the choanae. The soft palate also forms the roof of the oral cavity
What is the roof of the nasal cavity formed by?
the cribriform plate of the ethmoid bone
Where does the olfactory epithelium containing CN I neurons lie?
just inferior to the cribriform plate on the septum and the superior lateral walls of the nasal cavity
What is the anterior wall of the nasal cavity bound by?
nasal bones and cartilage
What is the posterior wall of the nasal cavity bound by?
sphenoid bone
What does the nasal septum consist of?
septal cartilage (tip of the nose), perpendicular plate of the ethmoid, and the vomer
When you breath quietly, where does air go?
it is guided across the inferior concha and through the MIDDLE meatus. Some air does cross the olfactory epithelium near the roof of the nasal cavity, but only a small amount unless you sniff (as to smell) strongly and create the turbulence required to force more air across the olfactory receptors
Where does the sphenoid sinus drain to?
The posterior ethmoid air cells?
The anterior ethmoidal air cells, frontal, and maxillary ?
The middle ethmoid air cells?
1) the sphenoethmoidal recess, above the superior meatus.
2) superior meatus
3) the hiatus semilunaris
4) bulla ethmoidalis
Where is the sphenopalatine foramen located?
just posterior to the middle concha where the vertical portion of the palatine bone meets the sphenoid
Where are the greater and lesser palatine foramen located?
near the posterior end of the hard palate in the lateral aspect of the palatine bone where the vertical and horizontal plates meet
What bone is directly posterior to the palatine bone?
the pterygoid process of the sphenoid bone (and the body of the sphenoid bone)
What are the four paransala sinuses?
maxillary, frontal, ethmoid air cells, and sphenoid
Describe the route of the maxillary nerve?
courses through the pterygopalatine fossa, giving off several branches, some which pass through some small named foramina in the lateral wall, or through the greater and lesser palatine foramina DOWN into the oral cavity.
All of the maxillary nerve branches just described carry what?
GSA from the mucosa of the nasal cavity. Their cell bodies are in the trigeminal ganglion in the middle cranial fossa
What fibers run with the branches of V2 to the nasal cavity and roof of the oral cavity and palate to innervate mucus glands there?
postganglionic GVE fibers from the pterygopalatine ganglion (CN VII)
The branches of V2 that enter the sphenopalatine fossa do what?
they can either course along the lateral wall of the fossa or can navigate the roof of the fossa medially and descend down along the septum in the midline
Where is the pterygopalatine fossa located?
in between the maxillary and lateral pterygoid plate (lateral to the sphenopalatine fossa)
What branches does the maxillary n. give off in the pterygopalatine fossa?
the maxillary n. itself goes into the fossa and anteriorly into the orbit, but it gives off lateral nasal branches that pass through the SP fossa to distribute over the conchae. It also gives off greater and lesser palatine nerves that distribute into the roof of the oral cavity. The greater palatine n. runs anterior once passing through the greater palatine fossa and the lesser palatine n. runs posteriorly once exiting its fossa. Both these course lateral to the palatine bone (i.e. they DO NOT pass through the SP at the top)
What do the lateral nasal nn. from the maxillary n. innervate?
the conchae
What do ethmoidal nerves branch from?
the nasociliary n. (branch of V1)
What do the ethmoidal nerves innervate?
ethmoidal air cells, sphenoid sinus, lateral nasal wall (goes inside the SP fossa), and septum
What does the nasopalatine n. branch from?
posterior superior nasal nerve (from maxillary)
Where does the nasopalatine nerve run?
it arches along the middle of the septum (so it passes into the SP) on either side and descends obliquely toward the incisive canal
What does the nasopalatine n. innervate?
the septum and a small area of the hard palate around the incisive foramen
Where are olfactory nerves present?
the septum, superior concha, and the sphenoethmoidal recess. They project through the cribriform plate on the floor of the anterior cranial fossa and synapse in the olfactory bulb
The lateral nasal wall bears olfactory nerves where?
in the superior aspect, in the sphenoethmoidal recess, and on the superior concha. These are SA
General somatic sensation to the nose all comes from?
CN V
What are the sources of GSE in the nose?
the anterior ethmoidal nerve ( a branch of the nasociliary n.) has internal, lateral, and external nasal branches for the anterior of the lateral nose and septum. General somatic sensation to the posterior aspect of the lateral nasal wall is through superior and inferior posterior lateral nasal nerves from V2
What is the vestibule innervated by?
the internal nasal branch of the infraorbital n. from V2
The superior nasopharynx gets overlapping GSA supply from what two sources?
CN V and IX
What two arteries anastomose in the incisive foramen?
the greater palatine artery and the posterior septal branch of the sphenopalatine artery. Sphenopalatine from the top and greater palatine from the bottom
NOTE: The palatine artery (which splits into greater and lesser branches, DOES NOT enter the SP fossa). the sphenopalatine a. does through the SP
What artery runs with the nasopalatine n. on the septum?
the posterior septal branch of the sphenopalatine a.
What arteries run with the lateral nasal branches of the maxillary n. on the lateral nasal walls?
posterior lateral nasal branches of the sphenopalatine a.
What three nerves supply the septum?
1) septal branches of the anterior ethmoid n. of the nasociliary n. (itself a branch of V1)
2) the nasopalatine n. (from V2) (distributes to the septum and, after passing through the incisive canal, distributes to the anterior part of the hard palate)
3) olfactory n.
What are the sources of vascular supply to the septum?
1) anterior septal branches from the anterior ethmoid a.
2) posterior septal branches from the sphenopalatine a.
What is Kiesselbach’s plexus composed of?
anterior ethmoid branches, sphenopalatine a. branches, and lateral nasal branches of the sphenopalatine a.
The veins in the anterior superior aspect of the lateral wall drain to where?
through the foramen cecum (anterior to the crista galli) into the superior sagittal sinus, or into the ophthalmic vein which drains into the cavernous sinus
The veins in the posterior inferior aspect of the nasal cavity drain to where?
pterygoid plexus and dural sinuses. Thus, if any area of the nose is infected, it is possible to spread the infection to different parts of the brain
What is the hard palate formed from?
palatine processes of the maxilla and the horizontal plate of the palatine bone
What does the incisive canal conduct?
the nasopalatine nerve, the greater palatine a., and the sphenopalatine a. (these two anastomose)
What do the greater and lesser palatine canals and foramina form from?
the greater palatine canal leads inferior from the pterygopalatine fossa and split to form two canals near the posterior aspect of the hard palate
What are the greater and lesser palatine a. branches of?
the descending palatine a.
What do they greater and lesser palatine canals conduct?
the greater and lesser palatine a., n., and veins
NOTE: the greater and lesser palatine nn. not only innervate the hard palate, but also the lingual gingiva of the maxilla
The anterior and posterior ethmoidal arteries are branches of which artery?
ophthalmic a.
What arises from the posterior palatine spine?
the muscles uvulae, palatopharyngeus, and the palatoglossus and from the palatine aponeurosis
What does contraction of the muscles uvulae cause?
shortening of the uvula and changing of the contour of the posterior edge of the palate, helping in closing off the nasopharynx
What muscle is referred to as the velum of the palate?
the levator veil palatini
Where does the tensor veli palatini arise from?
scaphoid fossa of the sphenoid bone
Describe the route of the tensor veli palatini?
descends laterally from the sphenoid bone to the medial pterygoid plate and turns 90 degrees around the humans to insert by blending into the other pharyngeal muscles and palatine aponeurosis
Motor innervation of all the palatine muscles, except tensor veli palatini is via?
pharyngeal fibers of the vagus
What is the tensor veli palatini innervated by?
V3
Sesnory to the palatine muscles is via?
lesser palatine nerve
What is origin of the levator veli palatini?
apex, petrous portion of the temporal bone
The palatine aponeurosis is attached to what?
the posterior border of the hard palate (i.e. the horiztonal plate of the palatine bone)
What muscles attach to the palatine aponeurosis?
tensor veli palatini levator veli palatini musculus uvulae palatoglossus, and palatopharyngeus
The palatine aponeurosis is strengthened by the insertion of the tendon of which muscle?
the tensor veli palatini
The auditory tube is aka?
pharyngotympanic tube or the Eustachian tube
The bony part of the auditory tube is part of which bone?
the temporal bone
Where is the vestibule of the oral cavity located?
a narrow area between the lips and cheeks and the teeth and gums
What is the associated muscle of the lips?
the orbicular oris
What is the associated muscle of the cheeks?
the buccinator
How many teeth are there and what are there surfaces referred to?
32; their anterior surfaces are called labial and their lateral surfaces are called buccal (externally facing) or lingual (internally facing)
What are the mandibular lingual gingiva innervated by?
lingual nerve
What are the maxillary lingual gingiva innervated by?
greater palatine and nasopalatine nn.
The right and left submandibular ducts empty into what?
the sublingual caruncles
The multiple ducts of the sublingual gland empty onto what?
the part of the mucous membrane called the sublingual fold
What is the fauces of the oropharynx?
it is the entry-way from the oral cavity to the pharynx (aka the oropharyngeal isthmus)
What are the tonsillar pillars made up of?
palatopharyngeal and palatoglossal folds
What fold marks the junction between the oral cavity and the pharynx?
the palatoglossal folds
The epiglottis is connected to the base of the tongue by folds int eh mucosa called?
the median and lateral glossoepiglottis folds
The valleys formed in between glossoepiglottic folds are called?
valleculae
Inflammed palatine tonsils would block which folds from view from the mouth?
palatopharyngeal
The anterior 2/3 of the tongue develops from which pharyngeal arch?
- the posterior 1/3 develops from 2
GSE to the anterior 2/3 of the tongue is via?
lingual branch of V3. taste fibers to this part of the tongue are from CN VII
The anterior 2/3 of the tongue is separated from the posterior 1/3 by what?
the sulcus terminalis
What lies at the center of the V separating the anterior and posterior tongue?
the foramen cecum where the thyroid gland began to develop in the floor of the mouth
The posterior 1/3 of the tongue develops from which pharyngeal arch?
2-4. Although since GSA is via CN IX, it’s main contribution is from 3
What tonsil lies directly behind the sulcus terminalis?
the lingual tonsil
What structures are included in the epiglottic region of the tongue?
the valleculae, the glossoeipglottic fold, and the epiglottis
What innervates the epiglottic region of the tongue?
GSE and SA via CN X through the internal branch of the superior laryngeal n.
After giving off innervation fibers to the stylopharyngeus m., how does CN IX course?
the main trunk of CN IX wraps around the lateral side of the stylopharyngess m, and enters the tongue in the gap between the superior and middle constrictor muscles and deep to the hyoglossus muscle
Where does the nasolacrimal duct drain?
drains tears from the eyes and empties into the inferior meatus
