Session 4: Oral Cavity and Upper GI Tract Flashcards
List the 3 sets of tonsils found in the upper GI tract
Palatine
Pharyngeal
Lingual
Between which 2 folds do the palatine tonsils lie?
Palatopharyngeal Fold
Palatoglossal Fold
Why does the GP gets you to say ‘aaaaaah’ when he inspects the inside of your mouth?
It raises the soft palate + uvula + depresses the tongue
Tests motor function of the vagus nerve.
Uvula should be midline
Problem: uvula deviates away from lesion
Describe the borders of the pharynx.
Base of the skull + inferior border of cricoid cartilage
What are the 3 parts of the pharynx and what are their borders?
Nasopharynx: down to the soft palate (pharyngeal isthmus)
Oropharynx: between the soft palate + epiglottis
Laryngopharynx: between the epiglottis + cricoid cartilage
What happens to the epiglottis when you swallow?
Retroflexion to cover the laryngeal inlet
What is the role of the soft palate in swallowing?
It elevates to close off the nasopharynx so food doesn’t go into the nasal cavity
What is the Piriform Fossa and what is its clinical significance?
Depressions on either side of the laryngeal inlet where food (e.g. fish bones) get stuck
Which muscles aid the passage of a bolus of food down the oesophagus?
Superior, middle + inferior pharyngeal constrictor muscles
Which nerves provide sensory innervation of the pharyngeal wall?
Glossopharyngeal + Vagus (pharyngeal plexus)
Which nerves provide motor innervation of the pharyngeal constrictor muscles?
Vagus (+ a bit of accessory)
Describe the changes that occur during swallowing.
Lift + retract tongue (styloglossus + intrinsic muscles)
Bolus into oropharynx (palatoglossus)
Close off nasopharynx by raising soft palate
Raise the larynx– closed off by the epiglottis
Peristaltic wave of constrictor muscles
Relax cricopharyngeus, open oesophagus
Name the 3 salivary glands, describe their secretions and state the nerves that provide secretomotor innervation to them.
Parotid: serous, glossopharyngeal
Submandibular: serous, facial
Sublingual: mucous, facial
Which muscle does the parotid duct pierce and where does it open into the buccal cavity?
Buccinator
It opens next to the 2nd upper molar
Name the main muscles of the tongue. Which nerve innervates all of this?
Genioglossus Hyoglossus Styloglossus Intrinsic Muscles Innervated by hypoglossal nerve
What other muscle is associated with the tongue but isn’t innervated by the hypoglossal nerve?
Palatoglossus – innervated by the vagus
What tongue movements do the genioglossus and styloglossus perform?
Genioglossus: protracts the tongue
Styloglossus: retracts + elevates the tongue
To which side would the tongue move if a patient with a unilateral lesion in the hypoglossal nerve was asked to stick their tongue out?
Towards the side of the lesion because the genioglossus is used in protracting the tongue
What movement is palatoglossus responsible for?
Elevates the soft palate + moves the back of the tongue upwards
Where is the lingual nerve relative to the hypoglossal nerve?
Lingual nerve is superior to the hypoglossal nerve
Describe the sensory innervation of the tongue
Anterior 2/3 sensation: mandibular branch of trigeminal
Anterior 2/3 taste: facial
Posterior 1/3 everything: glossopharyngeal
To which structure in the brainstem do the neurons of taste go? It is considered the main taste centre within the brainstem.
Nucleus Solitarius
State the origin and insertion of the masseter and the movement that it is responsible for.
Zygomatic Arch to Lateral surface of the ramus of the mandible + angle of the mandible Elevates mandible (allows forced closure of the mouth)
State the origin and insertion of temporalis and the movement that it is responsible for.
Temporal Fossa to Coronoid Process of mandible
Elevates + retracts mandible
