Superficial Face Flashcards
When do facial structures develop?
during 4th to 8th week around upper part of primitive pharynx known as primordial stomodeum(future mouth)
Oropharyngeal membrane layers
Outside ectoderm, inside endoderm
Oropharyngeal ruptures when and allows what into pharynx?
End of 4th week(26 days), allows amniotic fluid to pass into pharynx
What are the five prominences(facial primordia) that begin to appear around the large stomodeum during 4th week?
Single frontonsasal prominence, paired maxillary prominence, paired mandibular prominence
Frontonasal prominence
surrounds the ventrolateral part of the forebrain, has a frontal and nasal part(Duh!), frontal part forms forehead, nasal part forms upper part of stomedium and the nose
Maxillary prominence
Produced by neural crest cells that migrate from the neural fold into the prominence, form lateral boundary of stomodeum, move medially to meet other prominence, gives rise to maxilla and palatine shelves
Mandibular prominence
Produced by migration of neural crest cells, forms caudal boundary of primitive mouth(stomedium), gives rise to mandible and lower lip
Cleft lip and/or cleft palate
primitive tissue lobes grow:
one from the top of the head down towards the future upper lip; (Frontonasal Prominence), two from the cheeks, which meet the first lobe to form the upper lip; (Maxillar Prominence), and just below, two additional lobes grow from each side, which form the chin and lower lip; (Mandibular Prominence)
If these tissues fail to meet, a gap appears where the tissues should have joined (fused).
First arch of pharyngeal arch
Muscles of mastication, mylohyoid, anterior belly of digastric, tensor, tensor tympani, tensor veli palatini, Trigeminal nerve is the nerve(CN V)
Second Arch
Muscles of facial expression, stylohyoid, posterior belly of digastric, hyoid bone, CN VII
CN V - Opthalmic division V1. Name innervation and branches.
Sensory to forehead. Supraorbital - sensory to lateral forehead and upper eyelid, supratrochlear - sensory to medial forehead and upper eyelid, infratrochlear - sensory to medial part of eye and root of nose
CN V - maxillary division. innervation and branches.
Sensory to skin between lower eyelid and upper lip and skin over zygomatic bone and nose. Infraorbital nerve - sensory to skin of lower eyelid,check,lateral nose and upper lip,and skin over the anterior part of temporal fossa.
CN V- Mandibular division. innervation and branches.
Sensory to skin over mandible. Mental nerve - sensory to skin of chin and lower lip. buccal nerve - sensory to skin and oral mucosa of cheek, auriculotemporal nerve - sensory to scalp anterior to ear and posterior part of temporal fossa
Great auricular nerve
branch of cerivical plexus. sensory to skin inferior to ear and over parotid gland
Trigeminal Neuralgia(tic douloureux)
Disorder of sensory root of CN V. sudden sharp excruciating pain on the face, can last for 15-20 mins, maxillary nerve is usually involved.
muscles of facial expression
lie in superficial fascia, attached partly to skin, enables facial expression, no bone movement, all innervated by CN VII, muscles arranged around natural openings and act as sphincters.
Orbicularis Oculi
Sphincter of orbit. Orbital and palpebral part, produces crows feet - wrinking of skin lateral to orbit.
Muscles of nose
Sphincters of nose, poorly developed
Muscles of mouth
act as sphincters of oral cavity, depressor anguli oris, zygomatic major/minor, levator labii superioris, levator anguli oris, depressor labii inferioris, buccinator, oribicularis oris, platysma
Depressor anguli oris
Triangular muscle, depresses corner of mouth
Zygomatic major and minor
extend from zygomatic bone to corner of mouth, act to raise corner of mouth and upper lip
Levator labii superioris
descends from the infraorbital margin to upper lip, acts to raise upper lip
Levator anguli oris
extends from maxilla to corner of mouth, raises the corner of mouth
Depressor labii inferioris
attached inferiorly to mandible and superiorly blends with orbicularis oris, depresses lower lip
buccinator
attached to alveolar processes of mandible and maxilla and the pterygomandibular raphe. aids in mastication(not a muscle of mastication). keeps check taut - prevents biting of cheeks, used for whistling and chewing
Orbicularis oris
sphincter of oral cavity. encircles mouth and forms the prominence of the upper and lower lips. when tonically contracted, mouth is closed. compresses lips against teeth, holds food during mastication.
Muscles of scalp
Considered one muscle - Occipitofrontalis. Occipitalis, frontalis, two bellies of muscle are interconnected by tendinous sheath known as epicranial aponeurosis, no bony attachment, produces a suprised look when contracted.
Facial nerve exits through what and enters where?
Exits through skull through the stylomastoid foramen and enters the parotid gland.
Facial nerve has how many branches and name them.
5 branches. Temporal, zygomatic, buccal. mandible, cervical. (Two zebras bit my carrot, Yo!)
Bells Palsy
Injury to CN VII or its branches producing paralysis to some or all muscles of facial expression on one side
What branch of the external carotid artery is the facial artery?
4th branch
Facial nerve path
crosses mandible slightly anterior to angle and then follows a sinuous course across the face to medial angle of eye
Branches of facial artery
Inferior labial - for lower lip, superior labial - upper lip, angular - terminal part of facial artery at the medial corner of the eye
Superficial temporal comes of what artery?
terminal branch of external carotid artery, branches supply the face and scalp.
Branches of superficial temporal artery?
Transverse facial - follows parotid duct transversely across the face. Parietal - supplies lateral part of scalp, frontal - supplies the anterior part of scalp.
Facial vein origin and route
Begins as the angular vein at root of nose, no valves, makes connections with cavernous sinus and pterygoid plexus of veins.
