Oral Cavity Flashcards
What are the divisions of the oral cavity?
The oral cavity is divided into the vestibule and the oral cavity
What are the boundaries of the oral cavity?
Superior: Hard/Soft palate
Inferior: mylohyoid muscle
Anterior/Lateral: Teeth/gingiva & alveolar processes
Posterior: palatoglossal fold (oropharynx)
What are the foramen of the hard palate?
Incisive canal: midline located directly posterior to incisor teeth
Greater Palatine foramen – located in the posterolateral region of the hard palate
Lesser Palatine foramen – located posterior to the greater palatine foramen
What passes through the foramen of the hard palate?
Incisive canal: Nasopalatine nerve and terminal branches of the greater palatine artery pass through
Greater Palatine foramen - Greater palatine nerve and artery pass through
Lesser Palatine foramen - Lesser palatine nerve and artery pass through
Innervation of the Levator veli palatini (pair)?
Pharyngeal plexus by way of the vagus nerve
Action of the Levator veli palatini (pair)?
Elevates palate - prime mover of palate.
Innervation of the Tensor veli palatini (pair)?
V3 (mandibular division of trigeminal)
Action of the Tensor veli palatini (pair)?
Tenses soft palate and opens auditory tube
Innervation of the Palatoglossus (pair)?
Pharyngeal plexus by way of the vagus nerve
Action of the Palatoglossus (pair)?
Raises tongue to close off oral cavity from oropharynx during swallowing; depresses the soft palate; forms arch
Innervation of the Palatopharyngeus (pair)?
Pharyngeal plexus by way of the vagus nerve
Action of the Palatopharyngeus (pair)?
Raises pharynx during swallowing and tenses soft palate.
Blood supply of the hard palate?
Greater palatine artery (branch of descending palatine artery) - enters through greater palatine foramen and anastomoses with the septal artery after the greater palatine artery passes through the incisive canal.
Blood supply of the soft palate?
Lesser palatine artery - enters through lesser palatine foramen.
Blood supply of the upper dentition
Posterior superior alveolar artery (branch of maxillary) – supplies molars, and anastamoses with branches from infraorbital artery.
Middle and Anterior superior alveolar arteries (branches of infraorbital) – middle supplies premolars; anterior supplies canine & incisors; anastamose with posterior superior alveolar artery
Sensory innervation of the hard palate?
Greater palatine nerve - via greater palatine foramen.
Nasopalatine nerve - via incisive canal (foramen) to innervate anterior aspect of hard palate.
Innervations of the soft palate?
Lesser palatine nerve
CN IX - somatic sensation (gag reflex)
Innervation of teeth of upper palate?
Posterior, Middle and Anterior Superior Alveolar nerves (branches of infraorbital nerve – V2) supply the teeth of the upper palate.
Posterior branches typically supply the molars
Middle branches supply the premolars
Anterior branches supply the canine & incisors
Innervation of mandibular teeth?
Mandibular teeth are supplied by the Inferior Alveolar nerve (branch of V3) and artery (branch of the maxillary artery)
What is the sulcus terminalis?
The oral and pharyngeal parts of the tongue are separated from one another by a V-shaped groove known as the sulcus terminalis
What provides motor innervation to the tongue muscles (Genioglossus, Hyoglossus, Styloglossus) ?
CN XII
Action of Genioglossus?
Wags the tongue
Action of Hyoglossus?
Depresses and retracts tongue
Action of Styloglossus?
Moves tongue superiorly and posteriorly
What is in the floor of the oral cavity?
Submandibular and sublingual salivary glands
Submandibular duct (Wharton’s duct)
Lingual nerve
Hypoglossal nerve
What is the course of the lingual and hypoglossal nerves and the lingual artery relative to the hyoglossus muscle?
Both the lingual and the hypoglossal nerves course lateral to the hyoglossus muscle, whereas the lingual artery runs medial to this muscle
Blood supply of the tongue?
Lingual artery.
Describe sensory innervation of the tongue.
Anterior two-thirds of the tongue:
- General sensation - lingual nerve (from V3)
- Taste - chorda tympani (from CN VII) is carried by the lingual nerve
Posterior one-third of the tongue:
General sensation and taste - glossopharyngeal nerve (CN IX)
Base of Tongue:
Taste – vagus (CN X)
Describe parasympathetic supply of the Submandibular & Sublingual Glands.
Submandibular & Sublingual Glands: Innervated by the motor branch of Facial nerve traveling in the Chorda Tympani, which synapses in the Submandibular ganglion. Post-ganglionic fibers continue on in the lingual nerve to tongue and glands. Sympathetic post-ganglionic fibers originate in the Superior cervical ganglion and travel with the blood supply (lingual a.) to reach the glands.
Describe parasympathetic innervation of the parotid gland.
Parotid Gland: GLOAP Glossopharyngeal nerve via the Lesser petrosal nerve synapses in the Otic ganglion. Postganglionic fibers follow the Auriculotemporal nerve into the Parotid gland. Sympathetic post-ganglionic fibers originate in the Superior cervical ganglion and travel with the blood supply (maxillary & superficial temporal aa.) to reach the parotid gland.
