Oral Cavity and Tongue Flashcards
What is the roof of the oral cavity?
- Hard palate (anteriorly)
- Soft palate (posteriorly)
What is the floor of the oral cavity?
- The muscular diaphragm of the mylohyoid muscles
- Geniohyoid muscles
- Tongue
What is the anterior border of the oral cavity?
- The oral vestibule
What is the posterior border of the oral cavity?
- The oropharyngeal isthmus
What are the lateral borders of the oral cavity?
- Cheeks formed by the buccinator muscle
Lined by buccal mucosa
Sensory innervation of the hard palate
- Greater palatine nerve
- Lesser palatine nerve
(Both of which are branches of V2)
Sensory innervation of the soft palate
- Lesser palatine nerve
Sensory innervation of the floor of the oral cavity
- Lingual nerve
There are 2 pairs of arches at the back of the oral cavity, what are these called and what are their attachments?
- Palatoglossal folds (anterior): cover the palatoglossus muscle which attaches palate to tongue
- Palatopharyngeal folds (posterior): cover the palatopharyngeus muscle which attaches the palate to the pharynx
Which 3 frenula exist in the oral cavity?
- Superior labial frenulum
- Inferior labial frenulum
- Lingual frenulum
Which duct emerges in the oral cavity close to the lingual frenulum?
The submandibular duct (Wharton’s duct)
What feature is present between the palatoglossal and palatopharyngeal folds?
The palatine tonsils
What seperates the anterior 2 thirds of the tongue from the posterior third?
Vallate papillae (in a V shape)- sulcus terminalis
What feature exists in the middle of the vallate papillae?
Foramen cecum (location which the thyroid gland develops from embryologically)
Taste and general sensation to the posterior third of the tongue is provided by which nerve?
The glossopharyngeal nerve
General sensation to the anterior 2 thirds of the tongue is provided by which nerve?
The lingual nerve
Taste sensation to the anterior 2 thirds of the tongue is provided by which nerve?
Chorda tympani (branch of facial nerve)
4 types of papillae of the tongue
- Vallate papillae: separating root of tongue from body
- Foliate papillae: sides of tongue
- Fungiform papillae: mushroom shaped
- Filiform papillae: most numerous, cone shaped
What are the 4 extrinsic muscles of the tongue?
- Genioglossus
- Palatoglossus
- Styloglossus
- Hyoglossus
Describe the genioglossus muscle
- Large fan shaped
- Originates from superior mental spines
- Inserts onto the entire length of the tongue
Describe the palatoglossus muscle
- Emerges from a superior aspect
- Originates from the inferior surface of the palatine aponeurosis
- Inserts onto the posterior aspect of the tongue
Describe the styloglossus muscle
- Connects styloid process to the tongue
- Originates from styloid process of temporal bone
- Inserts onto side of tongue
Describe the hyoglossus muscle
- Scoops up underneath tongue
- Originates from the hyoid bone
- Inserts onto side of tongue
What are the 4 intrinsic muscles of the tongue?
- Superior longitudinal muscle
- Inferior longitudinal muscle
- Transverse muscle
- Vertical muscle
Describe the function of the intrinsic muscles of the tongue.
Provide the bulk of the tongue itself, and are contained within the tongue.
Describe the superior longitudinal muscle
Fibres run from the front of the tongue to the back of the tongue.
Shortens tongue.
Describe the inferior longitudinal muscle
Fibres run below the superior longitudinal muscle.
Shortens and retracts tongue.
Describe the transverse muscle
Fibres run side to side.
Elongates and protrudes the tongue.
Describe the vertical muscle
Located between the superior and inferior longitudinal muscle.
Flattens and broadens the tongue.
What is the innervation of both the extrinsic and intrinsic muscles of the tongue?
Motor innervation for all muscles except palatoglossus muscle: hypoglossal nerve (CN XII)
Motor innervation for palatoglossus muscle: vagus nerve (CNX)
Describe the venous drainage of the tongue
- Deep lingual vein drains the dorsum and sides of the tongue
- Dorsal lingual vein drains the tip of the tongue
These 2 veins join and drain into the lingual vein (which runs alongside the lingual artery)
Describe the arterial supply of the tongue
- Lingual artery runs between the hyoglossus and genioglossus muscle to supply the tongue
- There are also deep and dorsal lingual arteries
Describe the sublingual gland
- Located more anterior than submandibular gland
- Sublingual duct (duct of Rivinus) enters oral cavity through sublingual fold
- Supplied by glandular branches of sublingual artery
Describe the submandibular gland
- Has a superficial and deep lobe separated by the mylohyoid muscle
- Wharton’s duct enters oral cavity through sublingual papilla lateral to lingual frenulum
- Supplied by glandular branches of facial artery
