The Nasal And Oral Region Flashcards
What separates the two nasal cavities?
A bony and cartilaginous nasal septum
Slightly inside the nostril is a dilation, the _____, that is lined by stratified non-keratinized squamous epithelium with vibrisae (for cleaning the air).
Vestibule
What kind of epithelium is found in the vestibule?
stratified non-keratinized squamous epithelium with vibrisae (for cleaning the air).
What part of the nose is lined by a respiratory type ciliated epithelium containing mucus-secreting goblet cells that trap particulate matter?
The cavities
What happens to the trapped particles in the nasal cavities?
They are swept by the cilia into the throat where they are swallowed.
The paired ___ form the bridge of the nose and articulate anteriorly with the 3 pairs of nasal elastic cartilage (superior, inferior and alar)
Nasal bones
With which two bones does the nasal bone articulate with?
The frontal bones and ethmoid bone
Note: ethmoid is a major contributor to the nasal cavity
The cribiform plate of what bone forms the roof the nasal cavity and its perpendicular plate contributes to the midline septum.
Ethmoid bone
Which nasal conchae are part of the ethmoid bone?
Superior and middle
Approximate to its central location, the __ articulates with 15 bones: they are the frontal, sphenoid, the paired nasal, maxillary, lacrimal, palatine, inferior concha bones and the vomer.
Ethmoid bone
What do the conchae do?
Cause the air to swirl, prolonging the exposure to the rich vascularization that warms the air
What is beneath each nasal conchae?
A meatus (space) with openings that drain adjacent sinuses.
What lies behind the superior concha?
A sphenoidal sinus
What separates the sphenoidal sinus from the superior conchae?
The sphenoethmoidal recess
The ____ form a portion of the posterolateral wall of the nasal cavity
Palatine bones
the ____ is a Medan partition consisting of bone and cartilage between the two nasal cavities. It is covered on both sides by a mucous membrane
The nasal septum
What is the bony septum comprised of?
The vomer and perpendicular plate of the ethmoid
What is the vomer?
An unpaired, thin midline plate of bone that completes the posterior part of the septum
The ___ fills in the anterior portion of the septum.
Septal cartilage
Note: posterior is bone
The _____ are epithelial-lined air spaces that help condition the air, add resonance to the voice, and reduce the weight of the head. Each opens into the nasal cavity
The paranasal sinuses
Where are the ethmoidal sinuses located?
In the ethmoid labyrinth.
The paired ___ (air cells) are thin walled cavities located in the ethmoidal labyrinth.
Ethmoidal sinuses
Note: they are divided into anterior, middle, and posterior groups but the numbers are variable
Where are the frontal sinuses located?
In the mid anterior region of the frontal bone
Where are the sphenoidal sinuses located?
Below the sella turcica
What sinus is vulnerable in disease of the pituitary gland ?
The sphenoid sinus
What are the largest sinuses ?
The maxillary sinuses
Where are the maxillary sinuses located?
Lateral to the nasal cavity and below the orbit
There is a meatus (space) beneath each of the concha and a triangluar ______ between the sphenoidal sinus and the superior conchae.
spheno-ethmoidal recess
What drains the posterior Ethmoidal air cells?
The superior meatus
Where is the Ethmoidal bulla located?
In the middle meatus
What is the Ethmoidal bulla?
A rounded elevation produced by the middle Ethmoidal air sinuses
What does the middle meatus contain?
Ethmoidal bulla
Hiatus semilunaris
What is the hiatus semilunaris ?
A deep semicircular sulcus below the bulla
What does the middle meatus drain?
Frontal sinus
Anterior and middle Ethmoidal air cells
Maxillary sinus
The inferior meatus is the largest and contains the opening of?
The nasolacrimal duct for tears
Note: the superior is the smallest
What recess receives the opening of the sphenoidal air sinus?
The sphenoethmoidal recess
What is a common condition that leads to swollen and engorged tissue of the nose. The infection can spread to the anterior cranial fossa through the cribiform plate, as well as the nasopharynx to the middle ear and the lacrimal apparatus through the nasolacrimal duct.
Rhinitis
The paired _____ are separate bones located in the lateral wall of the nasal cavity. They contribute to the hiatus semilunaris above and create an inferior meatus below.
inferior nasal conchae
Where does the ostium of the maxillary sinus open?
Above the hiatus semilunaris
What does the maxillary sinus required to drain?
Ciliary action
Note: This explains why the maxillary sinus is the most frequently infected of the sinuses.
What is a solution to the maxillary drainage problem?
A Caldwell-Luc fenestration (hole) on the anterior wall of the maxillary sinus
Where do the olfactory nerves synapse after they pass the cribiform plate?
On mitral cells in the olfactory bulb
What is unique of olfaction?
The information does not enter the thalamus
What are the 4 primary sources of blood to the nasal cavity?
Anterior and posterior Ethmoidal arteries
Sphenopalatine artery
Greater palatine artery
From where do the anterior and posterior Ethmoidal arteries arise? (Go to nasal cavity)
The ophthalmic artery of the orbit
This is a branch of the maxillary a. that courses along the hard palate to the incisive canal through which it enters the nasal cavity. Upon entry, each artery divides and sends branches to the lateral and medial walls.
The greater palatine artery
Note: There is also a small contribution from the superior labial branch of the facial artery to the nasal cavity.
What are primary veins that drain the nasal cavity?
Facial (anterior region)
Sphenopalatine vein (posterior)
From the nasal cavity, where does the sphenopalatine vein drain to ?
To the pterygoid venous plexus.
The rich blood supply makes the region of the nasal cavity susceptible to ___, in response to hypertension, nasal intrusion, injury and the delivery of drugs.
Epitaxis, extensive bleeding
Where is Little’s (aka Kiesselbach’s) are located?
In the anterior part of the vestibule, near the atrium of the middle meatus
What four arteries anastomoses in Kiesselbach’s area?
- Superior labial branch of the facial artery
- Sphenopalatine
- Greater palatine
- Anterior ethmoidal branch
What are the most susceptible arteries to epistaxis in little’s (Kiesselbach’s) area?
The sphenopalatine and greater palatine arteries
Blood in the veins associated with the maxillary artery drain into the ______; that in the anterior-most veins enters the _____; and that in the superior-most veins enters the _______.
(Nasal)
- pterygoid plexus
- facial vein
- cavernous sinus
What does sensation to the nasal cavity?
Anterior ethmoid nerve (V1) Sphenopalatine n (V2)
Nasopalatine nerve (V2)
The axons in this nerve are from 1st order
neurons whose cell bodies reside in the trigeminal ganglion. The axons leave
the ethmoid nerve, enter the nasociliary nerve in the orbit, and then course in
V1 to the ganglion.
What nerve is this?
Anterior ethmoid nerve
_________, the axons of the 1st order neurons join the maxillary
nerve to reach the trigeminal ganglion.
The Sphenopalatine nerve
Where is the primary sense of the nasopalatine?
Hard palate
A _____ nerve from the sphenoid courses along the nasal septum and exits through the incisive foramen. It is primarily sensory from the hard palate
Nasopalatine
The ______ is the terminal branch of the anterior ethmoidal n. and is important for Rhinoplasty. Anesthetizing this nerve, and the adjacent trochlear nerves, permits operations under local anaesthesia.
External nasal nerve
What is vulnerable when an ethmoid fracture occurs?
Ethmoid labyrinths
Note: these form a thin layer of bone separating the nasal cavity from the orbit
What can fracturing the ethmoid labyrinths cause?
It can create a continuity with the orbit that can result in exophthalmos upon blowing the nose and can interfere with the function of the SO muscle.
Displaced fragments of ethmoid bone can enter the anterior cranial fossa resulting in a variety of lesions, what are they?
A- Piercing the cribbiform plate will damage the olfactory bulbs causing
anosmia (loss of smell) and diminished taste.
B- Fragments of bone can also cause leakage of CSF into the nose
(Rhinorrhea) with the potential for meningitis.
C- Fragments that reach the brain can disrupt the blood brain barrier.
What make the beginning of the nasopharynx?
Palatoglossal and palatophryngeal mucosal folds (by the velum)
What are the boundaries of the oral cavity?
superiorly by the palate, inferiorly by the tongue and mylohyoid muscle, and anteriorly/laterally by the buccinator muscle and the lips covering the teeth and gums. It ends at palatoglossal & palatopharyngeal mucosal folds that overly the muscles of the same name.
What is the innervation of the cheek (Buccal) region?
By the Buccal branch of V3 (sensory) and the Buccal branch of the facial nerve to the buccinator muscle (Motor)
What is the floor of the mouth composed of?
The broad mylohyoid muscle that originates from a median raphe and inserts on the inner aspect of the mandible
What innervates the mylohoid muscle at the floor of the mouth?
V3 from mylohoid nerve (which also innervate anterior belly of the digastric )
What innervate geniohyoid?
Innervate by axons from C1 of the cervical plexus (hypoglossal)
The hard palate is composed anteriorly of the paired horizontal plates of the maxilla and posteriorly of the paired posterior horizontal plate of the ________.
Palatine bones
The ____ contains the greater and lesser foramina, for the nerves of the same name, that convert sensory information to the trigeminal ganglion via the maxillary nerve.
The hard palate
Thought what foramen do the greater palatine artery and the nasal-palatine nerve though?
The incisive foramen of the hard palate.
What is the muscle of the velum (soft palate)?
The musculus uvulus muscle
What is the soft palate composed of?
- The musculus uvulus muscle
- Tensor veli palatini (V3), levator veli palatini (X)
- palatoglossus and palatopharyngeus
- Uvula
What innervates the palatoglossus and palatopharyngeus?
Vagus (X)
Note: Remember that the palatoglossus is exceptional because it is not innervated by the
hypoglossal n.
___ is an elevation of the soft palate and contraction of the pharynx in response to a sensation that differs from that normally elicited by swallowing.
The gag reflex
How can the gag reflex be elicited ?
By touching either the soft palate or the posterior pharyngeal wall. (Prolonged or repeated touching can result in emesis/vomiting)
Note: the sensory component is considered to be via IX and the efferent by X.
What is a cleft lip?
A narrow gap in the skin of the upper lip that often extends to the bones of the upper jaw and upper gum.
What is a cleft palate?
Cleft Palate can include both the hard and soft palate all the way to the
uvula. It occurs due to the failure of fusion of the lateral palatine processes, the nasal septum, and/or the median palatine processes.
What disorder/s can result in a velo-pharyngeal inadequacy (VPI) whereby air enters the nasal cavity resulting in problems with feeding, speech, hearing, and frequent episodes of Otis media.
Cleft palate and cleft lip
The ____ are due to a combination of genetic and environmental factors, such as smoking or certain medications.
E.g.
For psoriasis or arthritis
The cleft palate/lips
A full set of teeth in each jaw contains?
4 incisors, 2 canines, 4 pre-molars and 6 molars
There are ___ deciduous teeth that are replaced by ____ permanent teeth.
20 and 32
What are the maxillary teeth innervated by?
The anterior, middle and posterior superior alveolar branches of the maxillary nerve.
Fractures of the _____ are serious and a fracture in the anterior region will often be accompanied by a fracture elsewhere.
Mandible
What two major types of protein secretion does saliva have?
Serous secretion containing ptyalin
A mucus secretion secretion containing mucin
What is ptyalin and mucin for?
Ptyalin (alpha amylase) for digesting starches
Mucin for lubricating and for surface protection
The ____ gland secretes almost entirely serous type while the _____ and ____ glands secrete both serous and mucin types
Parotid.
Submandibular and sublingual
What can radiation therapy cause related to eating?
Permanent hyposalivation de to injury to the oral mucosa containing the salivary glands
What is a serious problem that can interfere with swallowing?(condition)
Chronic dry mouth (xerostomia)
What can case xerostomia?
Drugs such as tricyclic antidepressants or radiation therapy
What is the submandibular gland enclosed in?
Investing layer of deep cervical fascia in the submandibular triangle
What divides the submandibular gland into superficial and deep parts?
The mylohyoid muscle
What arises from the deep part of the submandibular gland and runs in the plane of the deep part before opening at a papilla (caruncle), lateral to the frenulum of the tongue.
Wharton’s duct
Wharton’s duct is crossed by what nerve that must be spared in surgery on the gland or duct?
The lingual nerve.
What can block Wharton’s duct leading to sialolithiasis?
A tumor or by a sialolith (calucus).
Note: blockage results in pain upon salivation
What is the only gland salivary gland that is not encapsulated in fascia?
The sublingual gland
Where is the sublingual gland located?
In the sublingual fossa of the mandible between the oral mucosa and mylohyoid muscle
Most of the saliva produced by the sublingual gland enters what duct?
The submandibular duct: the rest is secreted into the oral cavity rethought small ducts along its length
What separates the tongue into an anterior 2/3 and poster 1/3? (They differ in appearance and innervation)
The sulcus terminalis
The ____ forms the main bulk of the tongue and is responsible for primary movements.
Genioglossus
What is the attachment of the genioglossus?
It is attached to the mental spine of the mandible and the hyoid bone and contractions depresses and protrudes the tongue
What does contraction of the genioglossus do?
Depresses and protrudes the tongue
The __ is thin, shaped like a quadrangle, and arises from the whole length of the greater Cornu of the hyoid bone.
Hyoglossus
What is the action of the hyoglossus?
Contraction depresses and retracts the tongue
What muscle passes almost vertically upward to enter the side of the tongue and forms a part of the floor of the submandibular triangle?
The hyoglossus
The glossopharyngeal nerve, and the lingual artery lie medial to the ____ and the hypoglossal nerve lies lateral.
Hyoglossus
What muscle arises from the anterior and lateral surfaces of the styloid process and from the stylomandibular ligament.
Styloglossus
What muscle pases downward and forward between the internal and external carotid arteries and blends with the fibers of the hyoglossus?
The styloglossus
What is the action of the styloglossus?
The styloglossus draws up the sides of the tongue to create a trough for swallowing. As a pair they also aid in retracting the tongue.
What can happen when the tongue is paralyzed?
It can fall back into the oropharynx resulting in asphyxiation
What artery supplies the tongue?
The lingual artery, a branch of the ECA
Taste is mediated by receptors found in so-called taste buds. These are associated with 3 of the 4 types of papillae that form the ridges and valleys of the tongue, what are those?
Filiform
Fungiform
Foliate
What papillae are cone shaped. They are the most numerous ad are widely distributed. They do not contain taste buds
Filiform papillae
What papillae are muschroom shaped and found at the tip and sides of the tongue?
Fungiforme papillae
What papillae form a seres of folds along the sides of the tongue?
Foliate papillae
What papillae are found just in front of the sulcus terminalis?
Circumvallate papillae
There are only about 12 of the ___ papillae, which appear as flat mounds surrounded by a trench
Circumvallate
Axons from Upper Motor Neurons in the tongue region of the homunculus decussate, descend in the corticobulbar tract, and synapse on lower motor neurons in the hypoglossal motor nucleus. The axons of the LMN travel in the hypoglossal n to all extrinsic m of tongue except the ____, which is innervated by CN X.
Palatoglossal muscle
from the anterior 2/3 of the tongue is via the _____. The pain and touch pathways parallel those from other regions that receive sensations from trigeminal neurons.
lingual nerve of V3
From the posterior 1/3 is via the ____ n. The cell bodies of the 1st order neurons are in the superior ganglion (as are all those that convey sensory information through this nerve). The cell bodies of the 2nd order neurons are in the pontine nucleus for touch and the spinal nucleus for pain. The 3rd order neurons reside in VPM of the thalamus and the information is sent to the tongue region of the sensory homunculus
Glossopharyngeal
What are the 5 basic tastes?
All taste sensations can
be described as a combination of these basic modalities. Compounds in food that mediate these sensations activate receptors in the taste buds resulting in action potentials that
propagate along the axons of 1st order neurons that comprise the gustatory pathways
Sour Sweet Salty Bitter Umami
Taste is treated as if it is a __ modality.
Visceral afferent
What are the 3 cranial nerves that contribute to the sense of taste?
VII, IX, X
Taste from the anterior 2/3 of the tongue is mediated by 1st order neurons whose cell bodies are in?
The geniculate ganglion of VII
The
information courses along the chorda tympani nerve to the geniculate ganglion and the central axons
of these neurons enter the medulla and course to synapse on 2nd order neurons with cell
bodies in the rostal region of the ___ nucleus
Solitary nucleus
The
information courses along the ______ nerve to the geniculate ganglion and the central axons
of these neurons enter the medulla and course to synapse on 2nd order neurons with cell
bodies in the rostal region of the solitary nucleus
Chord tympani
Where are the 1st order neurons from the posterior 1/3 of the tongue?
The inferior (petrosal) ganglion of IX
Taste from the area around the epiglottis is communicated by 1st order neurons in what ganglion?
Inferior (nodose) ganglion of X
Pathology in the oral region can manifest itself depending upon which nerves are damaged and at what point along their course. This especially true of the _____nerve that has, at various points along its course, axons for general sensation and taste from the
anterior 2/3 of the tongue, and pre-ganglionic parasympathetics to the submandibular and sublingual glands
Lingual
