Anatomy of the oral cavity- glands, tongue, swallowing Flashcards
Where does the oral cavity span from anteriorly–> posteriorly?
the oral cavity can be divided into 2 parts. what divides it and which 2 sections does this create?
anterior border of the oral cavity: oral fissure (opening between the lips)
posterior border of the oral cavity: oropharyngheal isthmus (opening of the oropharynx)
oral cavity is split into 2 parts divided by the upper and lower dental arches into the vestibule and mouth proper
what is the vestibule of the mouth?
how does it communicate with the mouth proper?
the duct of which gland empties into the veticule behind upper molar 2?
- the vestibule of the mouth is the space between the lips/ cheeks and the gums/teeth
- communicates with mouth proper by gaps behind molar no*3
- duct of parotid gland empties out into the vesticule secreting salivary juices
what are the broders of the mouth proper?
roof-
lateral walls-
floor-
roof- hard and soft palates
lateral walls- cheeks
floor- muscular diaphragm, geniohyoid muscles, tongue, salivary gland and duct
Roof-
- what 2 structures make up the palate?
- what epithelium covers the hard palate?
- what is the soft palate made of/
- what is the function of the soft palate?
- the hard and soft palate
The hard palate
- the hard palate is found anteriorly and it seperates the oral and nasal cavities
- the hard palate is covered by respiratory mucosa (ciliated pseudostratified columnar epithelium) superiorly and by oral mucosa inferiorly (stratified squamous epithelium)
the soft palate
- continuation of the hard palate
- muscular structure
- acts as a valve to:
- lower and therefore clsoe the oropharyngheal isthmus (this prevents the food bolus from entering the nasopharynx)
- elevate and seperate the nasopharynx from oropharynx
Cheeks- lateral wall
which msucle forms this?
what is the cheek lined by?
which nerve innervates the cheek?
buccinator muscle forms the wall
lined by oral mucosa (stratified squamous non-keritinsied)
innervated by buccal branches of the facial nerve
What makes up the floor of the oral cavity
- muscular diaphragm- comprised of bilateral mylohyoid muscles. this structure pulls the larynx forward during swallowing.
- geniohyoid muscles- pulls larynx forward during swallowing
- tongue- connected to the floor by the frenulum
- salivary glands + ducts
Sensory innervation of the oral cavity
largely via 2 nerves
- hard palate
- soft palate
- cavity floor
- tongue
- cheeks
- hard palate- greater palatine nerve and nasopalatine nerve (both branches of the V2)
- soft palate- lesser palatine nerve (branch of V2)
- cavity floor- lingual nerve (branch of V3)
- Tongue- special sensory fibres for taste via chorda tympani (branch of facial nerve)
- Cheeks- buccal nerve (branch of facial nerve
The tongue contains 8 muscles
how are they divided
by whether theyre intrinsic (4) or extrinsic (4)
intrinsic tongue muscles
- what makes them intrinsic?
- name correlates to their direction of travel- what are their names?
- overall what do they do to the tongue?
- what does each do to the tongue?
- motor innervation to them is via?
intrinsic tongue muscles only attach to other tongue muscles
with all 4 of them, their name correlates to their direction of travel:
- superior longitudinal- shorten tongue
- vertical- shorten tongue
- transverse- flatten tongue
- inferior longitudinal- flatten tongue
The above is their layout within the tongue
overall thay change the shape+size of the tongue
motor innervation is via the hypoglossal nerve
what are the 4 extrinsic tongue muscles
- where do they attach
- where do they insert
- what is their functions
- what is their innervation
Genioglossus
- function: inf fibres- protrude the tongue/// middle fibres- depress the tongue/// superior fibres- tip back and down
- innervation: motor via the hypoglossal nerve
- attach: mandibular symphysis and inserts: into the body of the hyoid bone
Hypoglossus
- function: depresses and retracts the tongue
- innervation- hypoglossal nerve
- attach: hyoid bone, inserts: side of the tongue
Styloglossus
function- retracts and elevates the tongue
innervation- hypoglossal nerve
attach: styloid process of the temporal bone insert: side of the tongue
Palatoglossus
function- elevates posterior part of the tongue closing the oropharyngeal isthmus
innervation- vagus nerve
attach-*** palatine aponeurosis ***insert- broadly across the tongue
name the 4 muscles
yellow- geniohyoidus
blue- genioglossus
green- hyoglossus
purple- styloglossus
innervation to the tongue
- general sensation anterior 2/3
- taste anterior 2/3
- general sensation posterior 1/3
- taste posterior 1/3
- what is the arterial and venous supply to the tongue
- lymphatics of the anterior 2/3 and posterior 1/3
damage to the hypoglossal nerve
LMN lesion (damage to nerve itself)- curve towards the damaged side when protruding
(((((UMN lesion (damage to nerve pathway)- curve away due to action of genioglossus???)))))))
arterial supply to the tongue- lingual artery (majority) + tonsillar artery (both branches of ECA)
drainage- lingual vein
The hard palate is composed of which 2 bony parts
hard palate contains (3) foramina/ canals
2 arches bind the soft palate:
what sits between these 2 arches
hard palate- palatine processes of the maxilla + horizontal plates of the palatine bones
- incisive canal- transmits the nasopalatine nerve
- greater palatine foramen- greater palatine nerve and vessels
- lesser palatine foramina- lesser palatine nerve
palatoglossal arches anteriorly and the palatopharyngeal arches posteriorly
between these 2 arches sits the palatine tonsils
5 muscles make up the soft palate
they are all innervated by? apart from x which is innervated by?
what are the 5 muscles that make up the soft palate and their functions and attachments
all innervated by the pharyngeal branch of the vagus nerve
apart from tensor veli palatini which is innervated by the medial pterygoid branch of V3
1) tensor veli palatini
- function: tenses soft palate
- attachments: origin- medial pterygoid plate of the sphenoid bone insertion: palatine aponeurosis
2) levator veli palatini
- function: elevation of the soft palate
- attachments: attach- petrous temporal bone + eustachian tube insert- palatine aponeurosis
3) palatoglossus
- function: pulls soft palate towards tongue
- atatchments: palatine aponeurosis. insert: side of the tongue
4) palatopharyngeus
- function: tenses the soft palate, drawing the pharynx anteriorly when swallowing
- attachments: poaterioer nasal spine and palatine aponeurosis to thyroid cartilage
5) muscularis uvulae
- function: shortens uvula
- attachments: post nasal spine and aponeurosis to the uvula