Oral cavity and submandibular regions Flashcards
what makes up the oral region?
A. Oral cavity B. Cheeks and lips C. Teeth and gingivae D. Tongue E. Tonsils F. Salivary glands G. Palate
what is the oral cavity ?
what is it bounded by laterally, posteriorly and superiorly?
A. Consists of oral cavity proper and vestibule.
B. The oral cavity is the proximal-most portion of the GI tract.
C. It is the space bounded by the lips/cheeks and teeth; posteriorly by the oropharynx; superiorly by the palate.
what is the vestibule ?
what controls the size of the oral fissure
where does the parotid duct open in the vestibule?
- Space between the lips/cheeks and teeth.
- Opens externally at the oral fissure between lips.
- Muscles of facial expression control shape/size of oral fissure.
- Parotid duct opens into the vestibule opposite the upper 2nd molar.
what are the boundaries of the oral cavity proper? lateral/anterior superior inferior posterior
- Lateral/anterior – teeth gums
- Superior – hard/soft palate
- Inferior – floor of mouth
- Posterior – fauces
what covers the lips externally? internally?
covered by thin skin externally
internally covered by mucus membrane
orbicularis oris does what to mouth?
a. Orbicularis oris – closes lips/mouth
levator labii superioris
elevates upper lip
levator anguli oris
elevates upper lip, widens mouth
zygomaticus major and minor
elevates upper lip, main smile muscles
risorius
stretches lips laterally
wide smile
levator labii superioris alaeque nasi
elevates upper lip, flares nostrils
depressor anguli oris
depresses lower lip, frown
depressor labii inferioris
depresses lower lip
frown, pout
mentalis
protrudes lower lip
innervation to upper lip?
innervation to lower lip?
- Upper lip – V2 via infraorbital branches
2. Lower lip – V3 via mental and buccal branches
what is the lymphatic drainage of the lips (2)
- Submental lymph nodes – medial part of lower lip
2. Submandibular lymph nodes – all other regions
what is the funciton of teeth
mastication, articulation
how many permanent teeth?
how many deciduous teeth
B. 32 permanent teeth; 16 deciduous (baby teeth)
how many incisors, canine, premolars, molars
- Incisors (4), canine (2), premolars (4), molars (6)
2. Typically appear around 6-8 years of age
what is the gingivae
mucus membrane and fibrous tissue attached to the alveolar processes of the mandible and and maxilla bones
also attached to neck of teeth
maxillary teeth are innervated by what?
mandibular teeth?
- Maxillary teeth – superior alveolar branches of V2
2. Mandibular teeth – inferior alveolar branches of V3
innervation of the maxillary gingivae
palatine portion
vestibular portion
a. Palatine portion
1. Nasopalatine n (V2)
2. Greater palatine n (V2)
b. Vestibular portion
1. Superior alveolar branches of V2
innervation of the mandibular gingivae
internal portion
external portion
- Mandibular teeth – inferior alveolar branches of V3
a. Internal portion
1. Lingual n (V3)
b. External portion
1. Buccal n (V3)
2. Inferior alveolar n, mental branch (V3)
where does most lymph from teeth and gingivae drain?
what are 2 exceptions to this?
- Most lymph drainage is to submandibular lymph nodes
- Exception: mandibular incisors drain to submental lymph nodes.
- Exception: 3rd maxillary molars drain directly to superior deep cervical lymph nodes.
what is the tongue?
what is it involved with in terms of function?
what are the parts of the tongue
B. Muscular, mobile organ involved in mastication, swallowing, articulation, and taste.
body
root
epiglottic portion
what is the body of the tongue?
root?
- Body
a. Anterior 2/3rds of tongue; ends anteriorly at apex
b. Mobile - Root
a. Posterior 1/3 of tongue
b. Anchored to mandible, hyoid, and styloid process.
what is the terminal sulcus
what does it separate
what is its embryonic origin
- Terminal sulcus
a. V-shaped groove on dorsum of tongue
b. Separates root from body
c. Represents embryonic site of oropharyngeal membrane.
what is the foramen cecum a remnant of
thyroglossal duct
what are 4 types of papillae
vallate, filiform (no taste buds) , fungiform, foliate
what is the frenulum of the tongue
attachments under tongue to lower lip and one under the upper lip
what are the three intrinsic muscles of the tongue?
what are the functions of each?
a. Longitudinal (shorten; retract tongue; also can curl tongue)
b. Vertical (flatten; broaden tongue)
c. Transverse (narrow; elongate tongue)
genioglossus attachments
- Origin – mental spines of mandible
2. Insertion – dorsum of tongue; from apex to hyoid
genioglossus innervation
action acting bilaterally and acting unilaterally
- Innervation – hypoglossal n.
- Function – acting bilaterally - protrudes tongue;
acting unilaterally – PUSHES tongue to opposite side
hyoglossus attachments?
- Origin – Hyoid bone
2. Insertion – inferolateral side of tongue
hyoglossus action and innervation
- Innervation – hypoglossal n.
4. Function – retracts; depresses tongue
styloglossus muscle attachments
- Origin – styloid process
2. Insertion – superolateral side of tongue
styloglossus innervation and function
- Innervation – hypoglossal n.
4. Function – retracts; elevates tongue
palatoglossus attachments
innervation
function
- Origin – soft palate
- Insertion – tongue
- Innervation – vagus n***
- Function – pulls tongue and soft palate together during swallowing
what is the motor innervation to the tongue?
hypoglossal nerve (GSE) to all muscles except palatoglossus ***
vagus nerve –> SVE to palatoglossus
hypoglossal nerve lesion?
Hypoglossal Nerve Lesion. When patient is asked to protrude tongue, tongue will deviate toward affected (paralyzed) side because functioning genioglossus muscle pushes tongue contralaterally.
sensory innervation of anterior 2/3 of tongue (2 components)
GSA = lingual branch of V3 (NOT GVA) SVA = facial nerve via chorda tympani
sensory innervation (2 components) to posterior 1/3 of tongue
GVA–> glossopharyngeal n.
SVA –> glossopharyngeal n.
sensory innervation to eppiglottic region of tongue (2 components)
Hypoglossal Nerve Lesion. When patient is asked to protrude tongue, tongue will deviate toward affected (paralyzed) side because functioning genioglossus muscle pushes tongue contralaterally.
what is the arterial supply to the tongue
lingual artery- branch off external carotid artery
branches: dorsal lingual (posterior tongue, palatine tonsil)
sublingual (floor of mouth)
deep lingual (anterior tongue)
what is the venous drainage of the tongue ?
where do they course to as their final ending /
lingual veins
drain tongue and floor of oral cavity to the internal jugular vein
what are venae comitantes hypoglossi
drain floor of oral cavity and parallel course of hypoglossal nerve to end in the common facial vein.
what is the lymphatic drainage of the posterior 1/3 of the tongue
superior deep cervical lymph nodes (bilaterally)
what is the lymphatic drainge of the anterior 2/3 of the tongue
lateral sides–> submandibular ipsilateral
middle –> inferior deep cervical nodes (bilateral)
apex–> submental (medial portion draining bilaterally)
what are the 4 tonsils ?
what do they form>?
lingual
pharyngeal
palatine
tubal
B. These 4 groups form a defensive ring of lymphoid tissue referred to as the pharyngeal lymphoid ring or Waldeyer’s ring.
lingual tonsil
located deep to mucosa of posterior 1/3 of tongue
pharyngeal tonsils
located within pharyngeal recess of nasopharynx right under occiptial bone
palatine tonsils
located at the openings of oropharynx,
between palatoglossal and palatopharyngeal arches
tubal tonsils
located at the opening of auditory tube
what are adenoids
when pharyngeal tonsils are inflamed
what is the problem with enlarged lymph nodes
become englarged and occlude surrounding structures (fauces, opening to auditory tube; nasopharynx).
what is the function of salivary glands?
A. Secrete salivary fluid into oral cavity which functions to: begin process of digestion, lubricate food, prevent tooth decay, moisten oral cavity.
what are the three salivary glands
parotid
sublingual
submandibular glands
sublingual glands
location
what do they form
open into what via what?
- Lie in floor of oral cavity; covered with oral mucosa.
- Forms sublingual fold on floor of mouth.
- Open into oral cavity via several small ducts on sublingual fold.
submandibular glands
location (b/w what two muscles)
where does its duct course and open?
what nerve wraps around this gland as it courses forward
D. Submandibular glands
1. Superficial portion lies within submandibular triangle of neck; deep to mandible; superficial to mylohyoid muscle.
- Deep portion of gland wraps around the posterior border of the mylohyoid to pass between it and the hyoglossus muscle.
- Submandibular (Wharton’s) duct courses anteriorly from deep part of gland (between mylohyoid and hyoglossus) to open in floor of the mouth on the sublingual caruncle.
- NOTE: The lingual nerve wraps around the submandibular duct as they course forward.
where is the submandibular ganglion
what nerve is it suspended from
what does it contain
what does it provide innervation to
- Submandibular ganglion
a. Ganglion suspended from lingual nerve within posterior floor of oral cavity.
b. Contains the cell bodies of postganglionic parasympathetic fibers.
c. Provides innervation for the submandibular and sublingual glands
what are the boundaries of the submandibular region?
inferior
superior
roof
floor
- Inferior – anterior and posterior bellies of digastric muscles
- Superior – mandible
- Roof – cervical investing fascia
- Floor – mylohyoid muscle
what are the 4 main contents of the submandibular region
submandibular gland
facial artery
CN XII
Suprahyoid muscles
what are the 4 suprahyoid muscles
digastric
stylohyoid
mylohyoid
geniohyoid
digastric attachments
- Origin – anterior belly (digastric fossa of mandible)
– posterior belly (mastoid notch of temporal bone) - Insertion - hyoid
innervation and function of the digastric
- Innervation – anterior belly (V3); posterior belly (CN VII)
- Function – depresses mandible; elevates hyoid
what are the attachments, innervation and function of the stylohyoid
- Origin – styloid process
- Insertion – hyoid
- Innervation – CN VII
- Function – elevates and retracts hyoid
attachments of the mylohyoid
- Origin – mylohyoid line of mandible
2. Insertion – midline raphe and hyoid
innervation and function of the mylohyoid
- Innervation – mylohyoid branch of V3
4. Function – elevates hyoid and floor of mouth; assists with opening mouth
what are the attachments, innervation and function of the geniohyoid
- Origin – mental spines of mandible
- Insertion – hyoid
- Innervation – C1 via hypoglossal
- Function – elevates hyoid; when hyoid fixed, opens mouth
what is the paralingual space
posterior region of oral cavity between hyoglossus and mylohyoid mm.
what is the major artery in the submandibular region?
- Lingual artery – branch of external carotid artery
a. Dorsal lingual a. (posterior tongue)
b. Sublingual a. (floor of mouth)
c. Deep lingual a. (anterior tongue)
what veins are in the submandibular region
lingual vein –> drains to internal jugular vein
venae comitantes hypoglossi –> veins which parllel course of hypoglossal nerve and end in the common facial vein
sublingual absorption of drugs?
Sublingual Absorption of Drugs – certain drugs (such as nitroglycerin) need rapid absorption. Because the lingual veins drain directly to the IJV, drugs can be placed in the sublingual region (below the tongue on floor of mouth) and rapidly absorbed into the bloodstream.
what are the four major nerves to the oral cavity
lingual nerve (V3)
hypoglossal n.
glossopharyngeal
vagus nerve
lingual nerve to oral cavity branch of what? enters oral cavity where? courses in what space? wraps around what structure what does it pierce?
a. Branch of V3
b. Enters oral cavity posteriorly from infratemporal fossa.
c. Courses through paralingual space (between hyoglossus and mylohyoid mm.)
d. Wraps around submandibular duct in course.
e. Pierces tongue laterally.
what component does the lingual nerve provide
GSA to the floor of the mouth and anterior 2/3 of tongue
what does the lingual nerve distribute ?
SVA
GVE-P
both via chorda tympani
chorda tympani
branch of what nerve?
where does it exit the middle ear?
what does it merge with to travel to the oral cavity
what does it carry?
a. Chorda tympani is a branch of CN VII given of within middle ear.
b. Chorda tympani n exits middle ear via petrotympanic fissure to enter infratemporal fossa.
c. Here, it merges with the lingual n (V3) to travel to the oral cavity.
d. Carries
1. SVA to anterior 2/3rds of tongue
2. GVE-P (parasympathetic fibers) to submandibular ganglion to be distributed to the submandibular and sublingual glands.
hypoglossal nerve to the oral cavity
enters oral cavity where
what artery does it pass over and what space does it enter
what does it provide and to what structures ?
- Enters oral cavity from submandibular region.
- After passing lateral to the occipital artery, the hypoglossal nerve then enters the paralingual space.
- Provides:
a. GSE – extrinsic tongue muscles (except palatoglossus)
b. GSE – intrinsic tongue muscles
glossopharyngeal nerve in oral cavity
enters oral cavity where?
what muscles does it pass between
where does it pierce the tongue
what components does it provide
- Enters oral cavity posteriorly from pharyngeal region.
- After passing in between the superior and middle constrictor muscles, CN IX travels forward to pierce the tongue posteriorly.
- Provides:
a. GVA – posterior 1/3 of tongue
b. SVA – posterior 1/3 of tongue
vagus nerve in the oral cavity
what branch off vagus will enter the oral cavity
between what muscles does it pass on its way to oral cavity
what components does it provide?
- Internal branch of superior laryngeal nerve will enters oral cavity posteriorly from pharyngeal region.
- After passing in between the middle and inferior constrictors muscles, the internal laryngeal nerve will ascend to supply the epiglottic region of the tongue
- Provides:
a. GVA – epiglottic region of tongue
b. SVA – epiglottic region of tongue
