Anatomy of the Neck and Oral Cavity Flashcards
Cranial Nerves
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Degluttition:-
- swallowing
Lips and Cheek:
- lips contain muscle fibres from
orbicularis oris sphincter muscle which
encircles mouth = biggest muscle of
mastication - buccinator is also muscle of facial
expression which makes up the cheek
Lips and Cheek:
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Mouth and Oral Cavity:
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Trigeminal Nerve:
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Teeth:
- upper maxillary teeth are embedded in the
maxillary bones - lower mandibular teeth are embedded within
the mandibular bone - innervated by the maxillary,
mandibular branches = sensory
innervation to the teeth
Teeth:
What are the muscles of mastication?
Kemporalis
Salivary Glands:
3 paired salivary:
- parotid = glossopharyngeal CNIX
- submandibular = facial CNVII
- sublingual = facial CNVII
Salivary Glands:
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The muscles of mastication are a group of muscles which collectively move the ———
mandible with respect to the facial skeleton
Name the highlighted structures on the picture below.
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Tongue Composition:
- two groups of skeletal muscles:
- intrinsic muscles
- extrinsic muscles
Intrinsic Muscles of the Tongue affect the tongue by
changing the shape of the tongue, superior to the extrinsic muscles of the tongue
Extrinsic Muscles of the Tongue affect the tongue by
changing the position of the tongue, inferior to the intrinsic muscles of the tongue
extrinsic muscles of the tongue attach to bones like muscles and hyoid bone
The skeletal muscles of the tongue are covered by a
mucous membrane
Motor innervation of the skeletal muscles of the tongue from
the hypoglossal nerve (CNXII)
Name the extrinsic muscles of the tongue and which nerve supplies it:
- palatoglossus
- styloglossus
- genioglossus
- hypoglossus
All from hypoglossal nerve CNXII apart from palatoglossus which is innervated by the Vagus nerve CNX
Muscles of the tongue:
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Food travels through the oral cavity then
the pharynx and then the oesophagus which lies posterior to the trachea, (pharynx is the most posterior part of the oral cavity)
oral vestibule is
the space between teeth and lips when lips are closed
oral cavity is
the space behind the teeth
The inferior alveolar nerve runs within
the bones of mandible, provides sensory innervation to the lower teeth of the mandible
The superior alveolar nerve runs
within the maxilla
branch of the maxillary nerve
supplies sensory innervation to the upper teeth of the mandible
the inferior alveolar nerve enters the mandible through the
mandibular foramen
and comes around to innervate the front of the mandible through the mental foramen
The sublingual gland lies deeper than the submandibular under the tongue
True or False?
True
What is the parotid gland innervated by?
the glossopharyngeal nerve CNIX
Where does the submandibular gland drain?d
directly lateral to the frenulum of the tongue in the opening of the submandibular duct
Where does the sublingual gland drain?
lateral to the frenulum of the tongue and lateral to to the opening of the submandibular duct and hence opens in the sublingual duct
Where does the parotid gland drain?
in the oral vestibule
in the parotid duct
Extrinsic Muscles of the Tongue: Palatoglossus:
- runs from soft palate to tongue
- the soft palate is innervated by vagus
nerve - hence palatoglossus is also innervated
by the vagus nerve - helps move the tongue up and down
with the soft palate
Vallate Papillae
taste buds on the anterior 2/3 of tongue just anterior to the division of the tongue
lingual tonsils
located on the posterior 1/3 of the tongue
immune role
Tongue Innervation:
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What is the hard palate composed of?
- maxilla
- palatine bones
What is the soft palate composed of?
muscles covered by mucous membrane
Where is the soft palate located?
posterior to the hard palate
The uvula is a part of the hard palate.
True or False?
False
soft palate
Which nerve innervates the muscles of the soft palate?
innervated by the Vagus nerve CNX
Function of the soft palate:
elevated during swallowing to prevent food from entering the nasal cavity
Which of the two arches in the oral cavity is more posterior?
the palatopharyngeal arch
What lies between the palatoglossal and palatopharyngeal arch?
Palatine tonsils
lymphoid tissue
Soft Palate:
What nerve innervates these structures?
Pharynx function:
swallowing, breathing, resonance in speech
Differences between the larynx and the pharynx:
- the larynx is cartilaginous
- the pharynx is muscular
Pharynx: Sensory Innervation:
Glossopharyngeal CNIX
Three Divisions of the Pharynx:
- nasopharynx
- oropharynx
- laryngopharynx
Pharynx:
Pharynx: Muscles:
Constrictors:
all constrict walls of the pharynx during swallowing and are innervated by the vagus nerve CNX
the superior oesphageal sphincter, opens and closes during swallowing to allow the passage of food into the oesophagus
Posterior View of the Pharynx:
constrictor muscles are stacked upon each other
Stylopharyngeus Muscle of the Pharynx: Action and Innervation:
- elevates the pharynx during swallowing
- innervation (motor) by the glossopharyngeal
nerve CNIX
Gag reflex is
The gag reflex is a response to touching the posterior pharyngeal wall (Glossopharyngeal nerve (CN IX)) and involves a brisk and brief elevation of the soft palate and contraction of pharyngeal muscles (Vagus nerve (CN X)).
Internal Lateral View of Pharynx:
both muscles elevate pharynx
motor innervation by the vagus nerve CNX
Most of the pharyngealmuscles are innervated by the
motor innervation of Vagus except stylopharyngeaus muscle which is innervated by the glossopharyngeal nerve CNIX
Larynx location:
complex structure composed predominantly of cartilage, which sits at the top of the trachea, and protects the lower airway.
it also contains the vocal cords
Laryngeal Skeleton:
hyoid bone = doesn’t articulate with any bone, suspended by muscle attachments
thyroid cartilage is inferior
cricoid cartilage is inferior and is a complete ring of cartilage, relatively narrow in the front but posteriorly is wide
arytenoid cartilage is lateral
corniculate cartilage is superior to the arytenoid cartilage
Laryngeal Membrane and Ligaments:
thyrohyoid = between thyroid and hyoid cartilages
cricothyroid = between cricoid cartilage and thyroid cartilage
quadrangular = inferior border makes up the vestibular fold; running from the epiglottis to the arytenoid cartilage
vestibular fold = false vocal cords
^^^only in posterior view
Larynx:
if you see the epiglottis = anterior part of the larynx
rima glottis is the space between the vocal folds
False vocal cords (vestibular folds) vs True vocal cords
- folding of mucosa on the quadrangular
membrane - actual straight ligaments that run from the front
of our voice box to the back
Extrinsic Laryngeal Muscles:
divided into from hyoid to mandible and from hyoid to clavicle
geniohyoid is part of the extrinsic tongue hence deeper to mylohyoid muscle
digastric muscles has two parts forming a sling
all muscles elevate the hyoid bone if suprahyoid
sternohyoid - sternum to hyoid bone
omohyoid = shoulder to hyoid bone, anterior to the jugular
sternothyroid = runs deep to sternohyoid bone
just above the sternothyroid is the thyrohyoid bone
infrahyoid muscles depress the hyoid bone
Intrinsic Laryngeal Muscles:
What type of movement to open up vocal cords by aretynoid cartilage?
rotational
Which muscle is involved in pitch control?
Cricothyroid muscle, contracts, brings the larynx down, tightens vocal cords and brings down the pitch of your voice
Innervation of the larynx:
- Vagus CNX
- gives off the superior laryngeal nerve which
branches into internal and external - internal laryngeal nerve supplies sensory
innervation to the internal surface of the larynx - the external laryngeal nerve travels further down
and pierces the cricothyroid muscle, providing
motor innervation - recurrent laryngeal nerve is another branch of the
vagus which supplies motor and sensory
innervation to the inferior part of the larynx
Innervation of the Larynx:
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A hoarse voice may suggest damage to which nerves?
the recurrent laryngeal nerves
controlling the abduction of your vocal folds
one side will not abduct, so vibration runs differently
A monotonous voice may be a sign of damage to which nerves?
the superior or external laryngeal nerve
muscle can not contract
pitch control lost
Surface Anatomy:
Thyroid Gland:
- location
- lobes
- C5-T1
- left and right lobe connected by a thin isthmus
Why does the thyroid gland have a rich vascular supply?
Endocrine
needs to secrete hormones
Thyroid Gland: Pyramidal lobe:
during development, thyroid gland begins in the oral cavity ultimately making its way down the neck
remnant of thyroid gland root
sometimes present
Thyroid Gland: Blood Supply:
- Superior thyroid artery is a branch of the external
carotid artery. The external carotid artery is a
branch of the common carotid artery which arises
from the aortic arch - Inferior thyroid artery is a branch of the
thyrocervical trunk (from subclavian) - thyroid ima artery is found in 10% of the
population and generally a branch of the
brachiocephalic trunk
Thyroid Gland: Blood Supply:
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Thyroid Gland: Venous Drainage:
- Superior thyroid vein drains into the internal
jugular vein, which joins with the subclavian vein
to become the brachiocephalic veins. Left and
right brachiocephalic veins join at the venous
angle to form the superior vena cava - middle thyroid vein drains into the internal jugular
vein - inferior thyroid vein drains into the
brachiocephalic veins
Thyroid Gland: Venous Drainage:
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Fascial Compartments of the Neck:
- superficial fascia of the neck is a thin layer of
subcutaneous connective tissue - 4 compartments of the neck surround by layers of
deep cervical fascia:
- investing (muscle, sternocleidomastoid, trap)
- pretracheal (anterior, trachea, oesophagus)
- prevertebral (posterior, vertebra)
- carotid sheath (carotid arteries, internal
jugular vein, vagus nerve)
***prevent the spread of infection within a compartment
Triangles in the neck are divided into
the anterior triangle which is further divided into four
sternocleidomastoid separates anterior from posterior
the posterior triangle
The Carotid Triangle:
- boundaries
- contents (3)
- sternocleidomastoid (lateral), omohyoid (anterior)
and digastric (medial) - common carotid artery
- internal jugular vein
- hypoglossal and vagus
Submandibular Triangle:
- boundaries
- contents
- mandible (superior), stylohyoid (posterior),
anterior belly of digastric (anterior) - submandibular gland
- facial artery and vein passes through
Submental Triangle:
- boundaries
- contents
- anterior belly of digastric (posterior), hyoid
(lateral) - just under chin
- suprahyoid muscles
- lymph nodes
Muscular Triangle:
- boundaries
- contents
- superior belly of omohyoid muscle (posterior),
hyoid (superior) - infrahyoid muscles
- thyroid gland
Posterior Triangle:
- boundaries
- contents
- sternocleidomastoid (anterior), clavicle (inferior),
trapezius (posterior) - inferior belly of omohyoid muscle which passes
posterior to the sternocleidomastoid - external jugular vein
- spinal accessory nerve CNXI
Lymphatics of the Neck:
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How many compartments contained in the neck?
4
The larynx is a cartilaginous skeleton consisting of — individual cartilages
9
Larynx has intrinsic hyoid muscles that act to aid swallowing and airway protection.
True or False?
False
Extrinsic hyoid muscles
Larynx has intrinsic muscles that all act to produce sound, allow breathing and protect the airway.
True or False?
true
Triangles
