Anatomy Flashcards
Anatomy of the Upper GI Tract - Seaneen McDougall (143 cards)
what are the 3 pairs of muscles responsible for closing the jaw?
Masseter
Temporalis
Medial Pterygoid
what is the pair of muscles responsible for opening the jaw?
Lateral Pterygoid
what is the nerve division which supplies the jaw muscles?
mandibular division of trigeminal nerve - CN V3
What is the name of the joint where the jaw moves?
temporomandibular joint
what are the different regions of the pharynx?
nasal pharynx
oropharynx
laryngopharynx
How many teeth are in a complete set of teeth?
32 teeth
When do people typically have their full set of teeth?
age 18 but is expected by age 25
Why should you always ask if the patient has any loose teeth or fillings?
they are a choking hazard or aspiration risk
what are the 3 pairs of major salivary glands?
parotid (just in front of ear)
submandibular (under the mandible)
sublingual (under the tongue)
there are also loads of minor salivary glands
Where do each of the major salivary glands ducts enter into the mouth?
parotid - on the cheek in line with the 2nd molar
submandibular
sublingual - many ducts at the base of the mouth
What does the CN VII supply?
Taste ant. 2/3rds tongue
Muscles of facial expression
Glands in floor of mouth
What is the function of the extrinsic muscles of the tongue?
to change the position of the tongue during mastication, swallowing and speech
What are the functions of the intrinsic muscles?
modify the shape of the tongue during function
What nerve supplies the muscles of the tongue?
All of the muscles of the tongue are supplied by CN XII (hypoglossal) except for the palatoglossus
What does the patient have to do when you are inserting an endoscope?
They have to swallow in order to override the gag reflex
What happens in swallowing?
- close the lips to prevent drooling (orbicularis oris & cranial nerve VII)
- the tongue (cranial nerve XII) pushes the bolus posteriorly towards the oropharynx
- sequentially contract the pharyngeal constrictor muscles (cranial nerve X) to push the bolus inferiorly towards the oesophagus
- at the same time the inner longitudinal layer of pharyngeal muscles (cranial nerves IX & X) contracts to raise the larynx, shortening the pharynx and closing off the laryngeal inlet to help prevent aspiration
- the bolus reaches the oesophagus
Where in the neck does the oesophagus sit?
Just posterior to the trachea
What are the structures which which cause constriction in the oesophagus?
Cervical constriction Cricopharyngeus muscle (the upper oesophargeal sphincter at rib 1, root of the neck) Thoracic constriction(s) due to the arch of aorta and the left main bronchus (posterior to the heart) Diaphragmatic constriction Result of passing through diaphragm lower oesophageal sphincter (C10), oesophagus then immediateky connects with the stomach
What is the articular tubercle?
The tubercle which lies just anterior to the TMJ and helps to prevent dislocation of the joint
What is the course of the CN V3?
It comes from the pons (part of the brainstem) through the foramen ovale to the muscles of mastication and the sensory area
What is the name for the upper dental arch?
maxillary
What is the name for the lower dental arch?
mandibular
What nerve is responsible for sensation of the superior half of the gums (gingiva) and the palate?
CN V2
What nerve is responsible for sensation of the inferior half of the gums (gingiva) and the palate?
CN V3