Face Flashcards
4 roles of the muscles of facial expression?
1) Act as sphincters and dilators controlling the various openings
2) Support the angles of the eyes and mouth
3) Prevent secretions dribbling on to the face
4) Communication - change the expression of the face
What is the nerve supply to the muscles of facial expression?
Facial nerve CN VII
What are the sensory and autonomic functions of the facial nerve?
Sensory - taste from the anterior 2/3 of the tongue
Autonomic - lacrimal gland, submandibular gland, sublingual gland
Which 2 muscles act as dilators of the eye?
Act to elevate the eyelid
1) Levator palpebrae superioris
2) Smooth muscle called superior tarsal (mullers muscle)
Paralysis of orbicularis oculi can lead to what serious complication?
Results in failure of the eyelid to close - can lead to corneal injury due to lack of protection and dryness
Which muscles acts as a sphincter for the mouth?
Orbicularis oris
What is the function of the buccinator muscle in neonates and in adults?
In neonates - for suckling reflex
In adults - presses cheek against teeth and pushes food out of this space and onto the molars
Which is the largest of the paired salivary glands?
The parotid
What interval does the parotid gland occupy?
The interval between the mastoid process and the origin of sternocleidomastoid posteriorly and the ramus of the mandible, which it overlaps, anteriorly
What does the parotid gland lie within?
The fascial parotid sheath which is continuous with the investing fascia of the neck
Name a condition in which the parotid gland becomes swollen and why this may be painful?
Parotid gland stones
The facial nerve travels through the parotid gland and inflammation of the parotid may lead to pressure on the facial nerve causing pain
Where does the parotid duct open in the mouth?
Near the second upper molar tooth
Which cranial nerve divides into its 5 terminal branches within the parotid gland?
The facial nerve
The facial nerve lies superficially in the parotid gland so is vulnerable to damage, name 2 situations in which the nerve may be at risk?
Inflammation of the parotid gland
Trauma to the face
Other than the facial nerve which 2 other important vessels lie within the parotid gland?
1) Retromandibular vein (drains into the internal jugular)
2) Deep to that is the external carotid artery
What 2 terminal branches does the external carotid divide into within the parotid gland and which way do these project?
1) Maxillary artery - projects anteriorly
2) Superficial temporal artery - projects superiorly
Which cranial nerve loops anterior to the internal and external carotids just superior to the bifurcation - where is it travelling?
The hypoglossal nerve - running towards the tongue
What are the 4 muscles of mastication?
1) Masseter
2) Temporalis
3) Medial pterygoid
4) Lateral pterygoid
What is the function of the masseter muscle?
Elevates the mandible - a muscle of mastication
What is the nerve supply to the masseter muscle?
Masseteric nerve from the anterior trunk of the mandibular nerve
Which muscle acts as a sphincter around the eye?
Orbicularis oculi
Which muscle lies above the orbit running posteriorly over the skull?
Frontalis muscle
The fibres of which muscle run upwards from the corner of the mouth, what do they do?
Zygomaticus muscle
Helps to elevate the corner of the mouth
Which muscle does the parotid duct run over?
The masseter muscle
Where does the masseter muscle extend from and to?
Extends from the zygomatic arch superiorly to the angle of the mandible inferiorly
At what point does the parotid duct enter the oral cavity, penetrating which muscle?
Once the parotid gland reaches the anterior margin of masseter it penetrates the buccinator muscle which forms the lateral wall of the oral cavity
What must be removed to reveal the buccinator muscle?
The buccal fat pad
What 2 important arteries does the maxillary artery give rise to?
Inferior alveolar - supplying the teeth
Middle meningeal artery
What is the most superficial muscle in the neck?
Sternocleidomastoid
Where does the sternocleidomastoid muscle extend from and to?
From the mastoid process on skull to the sternum and clavicle
Which vessel runs on the anterior surface of sternocleidomastoid?
External jugular vein
What forms the 3 borders of the anterior triangle in the neck?
Superior border - inferior border of mandible
Medial border - imaginary midline running to sternal notch
Lateral border - medial border of sternocleidomastoid
What are the 4 infra hyoid muscles, which 2 are more superficial?
More superficial 1) Sternohyoid 2) Omohyoid Deeper 1) Sternothyroid 2) Thyrohyoid
Which is the most superficial suprahyoid muscle and what muscle lies deep to that?
Most superficial = anterior belly of digastric
Deep to that = mylohyoid
Where does the mylohyoid muscle run from?
Runs from mandible, meets in midline where 2 halves interdigitate and then extends posteriorly to the hyoid bone
Mylohyoid is one of the muscles which forms the floor of what?
The mouth
The cricoid cartilage is what shape?
Resembles a sovereign ring and your just looking at the band
Why is the cricothyroid membrane an important region?
Can gain access to the airway by passing through this membrane
Where does the vagus nerve lie in relation to the carotid artery in the carotid sheath?
Deep to the carotid a.
What is the ansa cervicalis and where does it run?
Loop of nerves formed from C1,C2,C3
Gives rise to various nerves which go to supply some of the infrahyoid muscles
The anterior part of the loop runs down the anterior surface of the internal jugular vein
The posterior part of the loop runs posterior to the internal jugular vein
Does the internal or external carotid lie most laterally?
The internal carotid lies most laterally
Which 3 arteries come of the external carotid in the neck?
From superior to inferior
1) Facial
2) Lingual
3) Superior thyroid
Why may you only see 2 vessels coming off the external carotid in the neck region?
The lingual and facial may come off a joint stalk
What does the facial artery pass through?
The sub mandibular gland
