Clinical anatomy of face Flashcards
(55 cards)
What is the cranium
Skeleton of the head
What are the two parts of the cranium
Neurocranium (bony covering of brain and meninges)
- Roof called the calvaria
- Floor called the cranial base
- Eight bones (frontal (1), ethmoid (1), sphenoid (1), occipital (1), temporal (2), parietal (2))
Viscerocranium (facial skeleton)
- 14 bones, Frontal, temporal, sphenoid, ethmoid and maxillary bones are pneumatised
What does pneumatised bones mean
Air within the bones. For the frontal, sphenoid, ethmoid and maxillary bones, these are in the form of paranasal sinuses
What percentage of non-verbal communication does our face provide
80-90%
What are the two main nerves which innervate the face
Trigeminal nerve supplies sensory innervation to the face (ophthalmic, maxillary and mandibular divisions) as well as motor innervation to the muscles of mastication (masseter, temporalis, and the two pterygoid muscles – lateral and medial).
Facial nerve from a clinical perspective supplies the muscles of facial expression (branchial motor fibres/special visceral efferent), special sensory fibres (special visceral afferent; taste), general sensory fibres (general somatic afferent; ear), parasympathetic fibres (general visceral efferent – innervating the sublingual and submandibular salivary glands)
What parts of the face does each division of the trigeminal nerve supply
Ophthalmic nerve
-Forehead and scalp
-Frontal and ethmoidal sinus
-Upper eyelid and its conjunctiva
-Cornea (see clinical relevance)
-Dorsum of the nose
Maxillary nerve
-Lower eyelid and its conjunctiva
-Cheeks and maxillary sinus
-Nasal cavity and lateral nose
-Upper lip
-Upper molar, incisor and canine teeth and the associated gingiva
-Superior palate
Mandibular nerve
(Sensory supply)
-Mucous membranes and floor of the oral cavity
-External ear
-Lower lip
-Chin
-Anterior 2/3 of the tongue (only general sensation; special taste sensation supplied by the chorda tympani, a branch of the facial nerve)
-Lower molar, incisor and canine teeth and the associated gingiva
(Motor Supply)
-Muscles of mastication; medial pterygoid, lateral pterygoid, masseter, temporalis
-Anterior belly of the digastric muscle and the mylohyoid muscle (these are suprahyoid muscles)
-Tensor veli palatini
-Tensor tympani”
What is herpes simplex
Virus caused by herpes simplex virus. There are 2 types, Type 1 and Type 2 and around the mouth, Type 1 is more common the mouth and Type 2 around the genitalia.
It could cause a cold sore around the corners of the mouth, affecting the maxillary or mandibular territories.
What is VZV
Varicella zoster virus (VZV): Primary varicella zoster infection results in CHICKENPOX and can cause lung and airway disease like bronchitis or pneumonia. When it resolves the virus lays dormant in the ganglia (collection of cell bodies) and can reactivate in 10-20% of people resulting in shingles or herpes zoster
What are the muscles of mastication
Masseter (zygomatic arch-mandible)
Temporalis (frontal/parietal bones – coronoid process of mandible)
Pterygoids (lateral and medial)
What is the function of the lateral pterygoid
Both left and right acting at the same time will result in protraction of the mandible. When one acts on its own it results in deviation of the mandible to the opposite side
What does the masseter do
Elevates the mandible and closes the mouth
What is the function of the temporalis
Elevates the mandible and closes the mouth, retraction of the mandible
What does the medial pterygoid control
Elevation of the mandible, closure of the mouth
How many muscles are in the face
43 - arranged around orifices
supplied by facial nerve
What is the orbicularis oris
Originates from the maxilla and cheek muscles inserting into the lips – skin and mucous membrane of the lips. This is involved in pursing of the lips – think of the selfie pout
What supplies the orbicularis oris
Buccal branch of facial nerve
What is the buccinator
Originates from the maxilla and the mandible and extends down to blend with the orbicularis oris and the skin of the lips
Pulls cheeks inwards resulting in pushing food and fluid into the centre of the oral cavity
What supplies the buccinator
Buccal branch of facial nerve
What does the orbital part of the obicularis oculi muscle do
Strong closure of the eyes, thicker part of this muscle
What does the palpebral part of the orbicularis oculi muscle do
In the eyelids, can do soft closure of the eyes including blinking
What are the auricular muscles
Auricularis superior/ anterior/posterior muscles
Very small and vestigial in humans and few of us are able to easily move our ears voluntarily
Where does the parotid gland enter the mouth
Opposite the second upper molar
What major structures pass through the parotid gland
External carotid artery (and terminal branches – maxillary and superficial temporal arteries)
Retromandibular vein (superficial temporal and maxillary veins unite)
Facial nerve
What is Mumps
Mumps is caused by a paramyxovirus and the relevance here is that it can cause swelling of the parotid gland, and lymph nodes, including those inside the parotid gland. These swellings are painful and give a hamster appearance, and are sore as they stretch the fascia (connective tissue) which surrounds the parotid gland.
