The Oral Cavity Flashcards
What are the 3 major functions of the oral cavity?
Digestion, communication, breathing
What are the two divisions of the oral cavity?
Vestibule and mouth cavity proper
What controls the diameter of the oral fissure?
Muscles of facial expression - mainly obilcularis oris
Where does the duct of the parotid gland open out into the vestibule?
Opposite the upper second molar tooth
What does the roof of the mouth proper consist of?
Hard and soft palates
What does the floor of the mouth proper consist of?
Muscular diphragm (bilateral mylohyoid muscles)
Geniohyoid muscles
Tongue
Salivary glands and ducts
What do the geniohyoid muscles do to the larynx during swallowing?
Pulls it forward
What do mylohyoid muscles do to the larynx during swallowing?
Pulls it forward
What muscle forms the cheeks?
Buccinator
What innervates the hard and soft palates?
Greater palatine and nasopalatine nerves (branches of CN Vb)
What provides sensory innervation to the floor of the oral cavity?
Lingual nerve (branch of mandibular branch of CN V)
What provides sensory innervation to the cheeks?
Buccal nerve (branch of mandibular division of CN V)
What provides motor innervation to the tongue?
Hypoglossal nerve (and vagus nerve for palatoglossus)
What provides taste to the anterior 2/3 of the tongue?
Chorda tympani (CN VII)
What provides sensation to the anterior 2/3 of the tongue?
Trigeminal (V3)
What provides sensation to the posterior 1/3 of the tongue?
Glossopharyngeal nerve
What provides taste to the posterior 1/3 of the tongue?
Glossopharyngeal nerve
What are the salivary glands?
Submandibular, parotid and sublingual
What is the duct associated with the submandibular gland?
Wharton duct
What is the duct associated with the parotid gland?
Stensen duct
Where are most salivary gland stones located?
In submandibular glands
What is sialolithiasis?
Salivary gland stones
What can cause sialolithiasis (salivary gland stones)?
Dehydration, reduced salivary flow
Which tonsils are most commonly affected in tonsillitis?
Palatine
What are the boundaries of the nasopharynx?
Base of skull to upper border of soft palate (C1-C2)
What are the boundaries of the oropharynx?
Soft palate to epiglottis (C2-C3)
What are the boundaries of the laryngopharynx?
Oropharynx to oesophagus (C4-C6)
What is the pharynx?
A muscular tube that connects the nasal cavities to the larynx and oesophagus
Describe the innervation to the pharyngeal muscles
Mostly CN X apart from stylopharyngeus which is CN IX
What are the two types of muscles that form the walls of the pharynx?
Longitudinal and circular
What are the circular muscles of the pharynx?
Superior, middle and inferior pharyngeal constrictors
What do the circular muscles of the pharynx do?
Contract sequentially and constrict the lumen to propel a bolus inferiorly into the oesophagus
What are the longitudinal muscles of the pharynx?
Stylopharyngeus (CN IX), palatopharyngeus and salpingopharyngeus (also opens eustachian tube)
What do the longitudinal muscles of the pharynx do?
Shorten and widen the pharynx, and elevate the larynx during swallowing
What provides sensory innervation to the nasopharynx?
Maxillary nerve (CN Vb)
What provides sensory innervation to the oropharynx?
CN IX
What supplies sensory innervation to the laryngopharynx?
CN X
What is the arterial supply to the pharynx?
Branches of the ECA
What does the oropharynx contain?
Posterior 1/3 of tongue, palatine tonsils, lingual tonsils and superior constrictor muscle
Which lymph nodes become enlarged with tonsillitis?
Jugulo-digastric lymph nodes
What two parts is the inferior pharyngeal constrictor split into?
Thyropharyngeus and cricopharyngeus (area between the two is a weak area in the mucosa)
