Mouth, Tongue, Sublingual Space Flashcards
What are the two cavities of the mouth?
The oral cavity proper and the oral vestibule
What are the components of the oral vestibule?
Vestibular fornix, labial frenulum, and parotid papilla
What are the components of the oral cavity proper?
Uvula, palatine tonsil, palatopharyngeal arch, palatoglossus arch, soft palate
What are the outer borders of the mouth?
Philtrum, nasolabial grooves, labiomental groove
What are the components of the lips?
Skin, vermillion border, transitional zone, and labial mucosa
What are the three types of oral mucosa?
Lining mucosa, masticatory mucosa, and specialized mucosa
What are the properties of lining mucosa?
Stratified squamous non-keratinized epithelium (the unattached gingiva, found in labial/buccal mucosa, alveolar mucosa.
What separates the lining mucosa from masticatory mucosa?
The mucogingival line
What are the properties of masticatory mucosa?
Stratified squamous parakeratinized epithelium (attached gingiva or the gingiva proper), gingiva and hard palate
What are the properties of specialized oral mucosa?
It is on the dorsal surface of the tongue and functions like a masticatory mucosa
List oral mucosa by permability
sublingual > buccal > palatal (based on keratinization)
Components of the floor of the mouth
submandibular glands, sublingual glands, lingual frenulum, plica sublingualis, Bartholin’s duct, wharton’s duct, deep lingual vein, lingual gingiva
What does the submandibular gland empty through?
Wharton’s duct at sublingual papilla = sublingual punctum = sublingual caruncula
What does the sublingual gland empty through?
Via Bartholin’s ducts, under a crest of mucosa (fold) called plica sublingualis
What is ankyloglossia?
“Tongue-tied”, where tongue attachment to floor of mouth is continuous with lingual frenulum
What nerves innervate the oral cavity?
CN V2 (for roof of the mouth), CN IX, CN X, CN VII
Which muscles form the floor of the mouth?
Mylohyoid muscle and geniohyoid muscle
What are the suprahyoid muscles?
Elevators of the hyoid during eating and swallowing. Mylohyoid, Digastric muscle, stylohyoid.
What are the infrahyoids?
Muscles that pull down the hyoid during eating and speaking. Thyrohyoid, omohyoid, and sternohyoid.
What are the three general parts of the tongue?
Body, root, apex. There is the dorsum as well, which is the top of the tongue.
What are two muscle groups of the tongue?
Extrinsic and intrinsic muscle groups
What are the extrinsic muscles?
Genioglossus (XII), Hyoglossus (XII), Palatoglossus (X - muscle of the palate), Styloglossus (XII)
These muscles allow the tongue to move in space and control the position.
What are the intrinsic muscles?
Superior longitudinal - under dorsal mucosa (XII), Vertical - along lateral edges (XII), Inferior longitudinal - under ventral mucosa, Transverse - runs through the tongue. Facilitates changes in shape of the tongue.
What is the function of the palatoglossus?
It pulls tongue and palate together to narrow the oropharyngeal isthmus.
What is the function of the genioglossus?
It protrudes the tongue, bilaterally depresses, universally wags. Is fan shaped and has anterior attachments to the mandible and the hyoid. Also the largest muscle of the tongue.
What is the function of the styloglossus?
Retrudes, elevates sides with genioglossus to form a trough during swallowing.
What is the function of the hyoglossus?
depresses and retrudes the tongue.
What innervates the muscles of the tongue?
CN XII - the Hypoglossus
What are the functions of the longitudinal muscles?
They shorten the tongue. The superior longitudinal makes concave shape and flips the tongue up, and the inferior longitudinal makes a convex and flips the tongue down–attaches at side.
What are the functions of the vertical muscles?
Flattens and broadens the tongue
What are the functions of the transverse muscles?
Narrows and elongates the tongue for extension.
What are the papillae of the tongue?
Circumvalate papillae, foliate papillae, filiform, and fungiform
Discuss the circumvalate papillae
Located anterior the sulcus terminalis, “round valley” to clean out for tastes, has serous (von Ebner) glands, HAS TASTEBUDS
Discuss the foliate papillae
Located posterior border of tongue, contain variable amounts of lymphoid tissue, HAS TASTEBUDS
Discuss the filiform papillae
Numerous, general sensory, gives dorsum of tongue the texture, and is keratinized, NO TASTEBUDS
Discuss the fungiform papillae
Fewer, at distal 2/3 of dorsal tongue, mushroom shaped, high individual variability, HAS TASTEBUDS
What are taste buds?
Taste buds and taste receptor cells are clusters of 100 polarized neuroepithelial cells- TRC’s have taste pores that allow saliva and food in
What are the five basic qualities of taste?
Sweet, salty, bitter, sour, umami
What are the taste cell types?
1: most-abundant, glial like, salt transduction
2: contain receptors for sweet, bitter, umami –known as receptor cells
3: least common, sour detectors, function as relay cells – presynaptic cells
What are the types of taste receptors?
Class 1 GPCRs - G Protein coupled: bitter
Class III GPCRs: Sweet and Umami
Ion Channels: salt and sour
What is the motor innervation pathway of the tongue?
Medulla oblongata -> Hypoglossal canal -> Hypoglossal nerve (CN XII)
BUT: remember that palatoglossus receives motor innervation from the pharyngeal plexus
What provides sensory innervation of the tongue?
V3 (Mandibular -> lingual nerve), VII (intermediate nerve–taste via chorda tympani and lingual nerve), IX (taste plus general sensation via lingual branches), X (internal branch of superior laryngeal nerve - innervates the pharynx)
Describe the vascular pattern of the oral and pharyngeal region.
From the external carotid: ascending pharyngeal artery, lingual artery, and facial artery -> mental branch of inferior alveolar artery, superior and inferior labial artery
Describe artery flow to the tongue
External carotid -> Lingual artery -> dorsal lingual arteries (provides posterior with blood supply), deep lingual artery (supplies body of the tongue), sublingual artery (supplies floor of the mouth)
What vascularizes the body of the tongue?
Deep lingual artery and venae comitantes
What are the two sides of the hyoglossus?
Superficial (between mylohyoid and hyoglossus) and Deep (between hyoglossus and genioglossus)
What lies superficial to the hyoglossus?
lingual nerve, submandibular duct, hypoglossal nerve, and vena comitans of the hypoglossal
What lies deep to the hyoglossus?
glossopharyngeal nerve and lingual artery
