Lecture 5 (head pt 2) Flashcards
What are the nerves of the face? Describe them
1) CN VII: facial nerve, mostly motor (for facial expression)
2) CN V: trigeminal nerve, mostly sensory, has three named branches called V1-2-3
1) What does CNVII innervate?
2) What does it travel? Why is this unique?
3) Where does it exit the face?
4) Where is it located?
1) Internal acoustic meatus and muscles of facial expression
2) Goes through facial canal, which is the longest boney canal any nerve must traverse, so it’s at risk
3) Styloid mastoid foramen
4) Deep to parotid gland
1) What nerve innervates the top half of the head?
2) What does it transmit?
1) CNV (has 3 branches, V1-3. )
2) Just somatic sensory
What does CNI do?
Doesn’t really do much to skin, just to muscles in suboccipital triangle
What nerve allows for facial expression?
CNVII (7)
What are the 6 muscles of facial expression? What are they all innervated by?
1) Occipitofrontalis (assoc. w frontal belly and epicranial aponeurosis)
2) Occipital belly
3) Orbicularis oculi (orbital sphincter)
4) Orbicularis oris (oral sphincter)
5) Buccinator (cheek muscle)
6) Platysma
All innervated by CNVII
List what’s embedded in the parotid gland from superficial to deep
1) Parotid plexus of facial nerve
2) CN VII
3) Retromandibular vein
4) External carotid artery + lymph nodes
What is CNV?
Cranial Nerve V, Trigeminal nerve
What are the 3 parts of CNV?
1) V1 - ophthalmic (cornea, nose, forehead)
2) V2 - maxillary (cheeks, tiny piece of nose and top of teeth)
3) V3 - mandibular (mandible, some temporal)
What are the afferent and efferent components of the corneal touch reflex?
Afferent component is V1, motor component is CVII
What are the afferent and efferent components of the light reflex
Optic nerve is afferent, constriction would be CNIII’s sympathetic division
Where does each part of the trigeminal nerve exit?
V1: supraorbital foramen or notch
V2: infraorbital foramen
V3: mental foramen via mandibular canal
1) What do the lateral pterygoid muscles do? Where is it?
2) What about the medial pterygoids?
3) What are they innervated by?
1) Lateral pterygoid m. open mouth (gravity prime mover), protrudes chin
-goes from TMJ across zygomatic arch
2) Medial pterygoid m. closes mouth, protrusion
-goes from lateral part of angle of mandible to medial part of lateral pterygoid muscle
3) Innervated by anterior trunk mandibular n., CN V3
When contracted unilaterally, the lateral and medial pterygoid muscles do what?
Cause a lateral chewing motion, grinding motion
What is TMJ often mistaken as? Why?
Ear pain, because that joint is so close to the external auditory canal
1) What is TMJ?
2) How does it often manifest?
3) What are TMDs?
1) Temporal Mandibular Joint syndrome (TMJ)
2) Often manifests itself as “earache” in teens and adults
3) Temporomandibular disorders (TMD): a heterogeneous group of musculoskeletal and neuromuscular conditions involving the temporomandibular joint complex, and surrounding musculature and osseous components.
1) What percent of the population is affected by TMDs? When is peak incidence?
2) What are the two classifications of TMDs?
3) What are common symptoms of TMDs?
1) TMD affects up to 15% of adults, with a peak incidence at 20 to 40 years of age.
2) TMD is classified as intra-articular or extraarticular.
3) Jaw pain or dysfunction, earache, headache, and facial pain.
1) What is the etiology of TMDs?
2) How are TMDs diagnosed?
3) When may diagnostic imaging be beneficial?
1) Multifactorial; includes biologic, environmental, social, emotional, and cognitive triggers.
2) Diagnosis most often based on history and physical examination.
3) When malocclusion or intra-articular abnormalities are suspected.
1) How are TMDs improved in most cases?
2) What medications are recommended initially, and what medications are recommended for chronic cases?
3) What is recommended for refractory cases?
1) Most pts improve with a combination of: noninvasive therapies, including patient education, self-care, cognitive behavior therapy, pharmacotherapy, physical therapy, and occlusal devices.
2) Nonsteroidal anti-inflammatory drugs and muscle relaxants are recommended initially, and benzodiazepines or antidepressants may be added for chronic cases.
3) Referral to an oral and maxillofacial surgeon is indicated for refractory cases.
1) What are most arteries to the face branches of?
2) What are most external facial veins drained by?
3) Does this vary? If so, what are the alternate routes?
1) External carotid a.
2) Veins that accompany the arteries
3) Varies; alternate route include superficial and deep drainage
1) Where does the facial artery arise from?
2) What does it supply?
3) Can you palpate its pulse?
1) External carotid a.
2) It’s the major artery to superficial face
3) Yes
List the 5 branches of the external carotid artery that supply the face
1) Lingual a.
2) Facial a.
3) Occipital a.
4) Posterior auricular a.
5) Maxillary a
What two arteries that supply the face don’t originate from the external carotid? Where do they come from?
Supratrochlear and supra-orbital arteries are from internal carotid branches
1) What does the superficial temporal artery arise from?
2) What is one of its characteristics?
1) External carotid a.
2) Can palpate its pulse
What two arteries of the face can you palpate the pulses of?
Facial arteries and temporal arteries
1) What is an inflamed temporal artery called? (2 names)
2) What causes it?
3) What are its symptoms?
1) Temporal arteritis (Giant Cell Arteritis)
2) The cause of the blood vessel inflammation is unknown; maybe autoimmune?
3) Headaches, jaw pain, vision loss, fever, and fatigue