Lecture 32 - Oral Cavity Flashcards
What makes up the oral cavity proper?
Space internal to the teeth
What makes up the vestibule in the mouth?
Space between the lips/cheeks and the teeth
What are the three layers of the lips and cheeks?
Skin - Muscles/CT - Mucosa
What is major distinction between the lips and cheeks?
presence of the oral orifice
What is the frenulum?
Midline mucosal fold, fixes the tongue to the floor of the mouth
What is the root of the tongue attached to?
Basihyoid bone
What creates the valleculae in the caudal portion of the tongue?
midline mucosal fold to the epiglottis
medial glossoepiglottic fold
What is the function of the small keratinized filiform papillae on the dorsal surface of the tongue?
Protect it from sharp objects
What are the three types of papillae related to taste on the tongue?
Fungiform - Foliate - Vallate
What are Vallate papillae?
Largest papillae very caudal portion of the tongue
What is special about the feline tongue?
Keratinized filiform papillae are much larger and are directed caudally
What are the specialized papillae on a cats tongue called?
Conical papillae
What is the structure called in the tongue of cats and dogs that stiffens the tongue?
Lyssa
What are the two groups of tongue muscles?
Intrinsic and Extrinsic
What do the intrinsic tongue muscles form?
Dorsal and lateral parts of the body
What do the intrinsic muscles of the tongue do?
Control the shape and fine movements of the tongue
What are the intrinsic tongue muscles innervated by?
CN XII - Hypoglossal n.
Where do the extrinsic muscles of the tongue located?
Originate on other structures and insert on the tongue
What are the MOST of the extrinsic tongue muscles innervated by?
CN XII - Hypoglossal n.
What extrinsic tongue muscle is NOT innervated by the CN XII?
Palatoglossus
What is the origin of the genioglossus?
Medial surface of the mandible
Where does the genioglossus insert?
Midline ventral surface of the tongue
What does the genioglossus do?
Depress the tongue
What is the origin of the hyoglossus?
Basihyoid
Where does the hyoglossus insert?
Lateral side of the caudal portion of the tongue
What does the hyoglossus do?
Retract the tongue
Where does the styloglossus originate?
Stylohyoid
Where does the styloglossus insert?
Lateral surface of the tongue along most of the length
What does the styloglossus do?
Retract the tongue
Where does the geniohyoid muscle originate?
Intermandibular articulation
Where does the geniohyoid insert?
Basihyoid
What does the geniohyoid do?
Draws hyoid apparatus and larynx rostrally
What does the lingual artery comes from?
External carotid
When does the lingual artery come off the external carotid?
Where the hypoglossal nerve CN XII
Where does the lingual artery enter the oral cavity?
Medial surface of the hyoglossus muscle
What is the lingual artery run in relation to on the tongue?
Lateral surface Genioglossus muscle
What happens to the lingual artery as it reaches the apex of the tongue?
Deep lingual artery and vessels
What special function do the vessels have at the apex of the tongue?
Arteriovenous anastomoses - to facilitate heat exchange and cool animal during panting j
What does the hypoglossal n run with?
Lingual artery after crossing through cranial neck
Where does the hypoglossal n. enter the oral cavity?
Lateral surface of the hyoglossus muscle
What are the four cranial nerves that give sensory to the tongue?
CN V3 - Lingual N.
CN VII - Facial N.
CN IX - Glossopharyngeal n.
CN X - Vagus n.
What provides general sensory to the rostral portion of the tongue?
Lingual nerve
What provides taste to the rostral portion of the tongue?
Facial n.
How does the facial n. get to the rostral portion of the tongue?
Via chorda tympani hitchhiking on the lingual n.
What landmark shows you that you are in the rostral portion of the tongue?
Rostral to the vallate papillae
What does the Glossopharyngeal n. do in regards to the tongue?
Provides both sensory and taste to most of the caudal tongue
What does the vagal n. do in regards to the tongue?
Both general sensory and some taste of the tongue around the epiglottis
What are the four salivary glands?
Parotid - Mandibular - Sublingual - Buccal
What is different about the salivary glands in the dog?
Buccal gland has a dorsal region called zygomatic
Where is the duct of the parotid gland?
Runs superficially across the masseter
where does the parotid gland drain in the mouth?
Opposite of the fourth maxillary premolar
Where is the mandibular salivary gland?
Sandwiched between maxillary and linguofacial vein
What is the path of the duct of the mandibular salivary galnd?
Medial surface of the gland through the floor of the oral cavity to empty into the rostral part of the oral cavity
What are the two sublingual glands?
Monostomatic gland
– and –
Polystomatic gland
Where does the monostomatic gland drain?
Single major sublingual duct that runs parallel to the mandibular duct
Where does the polystomatic gland go?
Drain directly via numerous small ducts through the mucosa of the floor of the oral cavity
Where are the sublingual caruncle?
Small bump of tissue just lateral to the root of the lingual frenulum
What type of innervation do the salivary glands get?
SNS and PNS
What provide facial parasympathetics?
Pterygopalatine ganglion
Mandibular and sublingual gnaglia
What do the facial PNS axons synapse?
Otic ganglion
Where do the nerves from the otic ganglion go to?
Parotid and buccal/zygomatic glands
Where is the otic ganglion found?
Adjacent to CN V3 ventral to the oval foramen
Where to the presynaptic PNS from CN IX come from that go to teh otic ganglion?
Middle ear, middle cranial fossa, and foramen ovale
Where do postsynaptic PNS axons go from the otic ganglion?
Hitchhike on the auriculotemporal nerve
Where are the mandibular and sublingual ganglia found?
Adjacent to lingual nerve as it enters the oral cavity
Where do the preganglionic PNS come from in regards to the mandibular and sublingual ganglia?
Through the ear to the infratemporal fossa and join the lingual nerve
