Anatomy: Floor Of The Mouth Flashcards
What structures make up the roof of the oral cavity?
- hard palate
- soft palate
What structure makes up the posterior border of the mouth?
The oropharyngeal isthmus
What is the oropharyngeal isthmus?
A space bounded laterally by the palatoglossal folds
What structures compose the floor of the oral cavity?
The tongue and muscles of FOM
What structures make up the anterior border of the oral cavity?
The alveolar/dental arches
What structure is very tightly adhered to the periosteum of the maxilla and palatine bones?
Palatal mucoperiostium
What mucosa is made up of non-keratinised stratified squamous epithelium?
Alveolar mucosa
The point where the alveolar mucosa meets the attached gingiva is known as?
The mucogingival junction
The bands of tissue anchoring mucosa to underlying bone are known as?
Labial frenula
What are sublingual folds?
Openings in the FOM for ducts if sublingual gland to drain through
What is the purpose of sublingual papillae?
Openings for submandibular gland ducts
What vein is a feature of the FOM?
The deep lingual vein
What muscle forms the most inferior part of the FOM?
The anterior belly of digastric
What innervates the anterior belly of digastric?
CN V3 via the nerve to mylohyoid
Where does the superficial part of the submandibular gland sit in relation to the mylohyoid muscle?
Sits inferiorly
Where does the deep part of the submandibular gland sit in relation to the mylohyoid muscle?
Sits superiorly
Where does the left and right geniohyoid muscles sit in relation to the mylohyoid muscle?
Superiorly (deeper)
Where do the sublingual glands sit in relation to the mylohyoid and geniohyoid?
They sit superior to the mylohyoid and lateral to the geniohyoid
What cranial nerve supplies the geniohyoid?
CN XII (hypoglossal nerve)
What two structures in the floor of the mouth cross over one another, and how?
The submandibular duct crosses over the top of the lingual nerve
Where does the chorda tympani carry pre-synaptic parasympathetic fibres to synapse?
The submandibular ganglion
Where are post-syntaptic parasympathetic fibres from the submandibular ganglion distributed?
To both the sublingual and submandibular glands
Where does the chorda tympani relay special sensory fibres to?
Anterior 2/3rds of tongue
What are the 4 main functions of the tongue?
- forms food bolus to be swallowed
- keeps mouth clean
- speech
- tasting and sensing food
What nerve supplies general sensation to the anterior 2/3rds of the tongue?
The lingual nerve ( branch of CN V3)
What nerve supplies special taste sensation to the anterior 2/3rds of the tongue?
CN VII (chorda tympani)
Which nerve supplies general and special sensation to the posterior 1/3rd of the tongue?
CN IX ( Glossopharyngeal nerve)
What structure divides the anterior and posterior parts of the tongue?
The terminal sulcus
What nerve supplies vallate papillae?
CN IX
What nerve supplies foliate papillae?
CN VII
What nerve supplies filiform papillae?
CN V3
What nerve supplies fungiform papillae?
CN VII
Which papillae is an exception to the rule that CN IX only applies the anterior 2/3rds of the tongue?
Vallate papillae
Which papillae is not a taste bud? It functions to mechanically move food.
Filiform papillae
From the lateral side of the neck, explain the path of the hypoglossal nerve to reach the tongue.
- Passes between the internal carotid artery and internal jugular vein
- Passes inferior to anterior belly of digastric
- Passes into submandibular region, laterally to the hyoglossus muscle of the tongue
- Passes superiorly to mylohyoid in order to reach the tongue
What are the two types of straited muscles of the tongue?
Intrinsic and extrinsic
Which strained muscles act to alter the shape of the tongue?
Intrinsic muscles
What do longitudinal intrinsic muscles do to the tongue?
Make it short and thick
What do transverse and vertical intrinsic muscles do to the tongue?
Elongate and narrow it
What are the four main extrinsic muscles?
- palatoglossus
- styloglossus
- hyoglossus
- genioglossus
What extrinsic muscle can be considered the ‘main muscle of the tongue’?
Genioglossus
Where does the genioglossus arise from to insert into the body of the tongue?
Arises from genial tubercules or mental spines
What cranial nerve supplies all extrinsic muscles except the palatoglossus?
CN XII
What cranial nerve supplies the palatoglossus?
CN X
What happens to the tongue when the genioglossus muscle contracts?
The tongue sticks out
What is the clinical test for CN XII?
Ask patient to stick tongue out straight.
- if nerves are normal, tongue will remain in midline
- if nerves are damaged, tongue will point towards the side of injured nerve
The sublingual papillae serve as openings for saliva from which gland?
Submandibular gland
The labial alveolar mucosa extends between the boundaries of which teeth?
3-3 ( canine to canine)
