Muscles of eyes, mastication, soft palate, tongue Flashcards
Bone of that surrounds orbits
- frontal
- sphenoid
- zygomatic
- palatine
- maxilla
- lacrimal
- ethmoid
Lacrimal apparatus:path of tear
- lacrimal gland produces tears
-parasympathetic from CN VII facial n. - lacrimal ducts
- surface of eye
- lacrimal lake
- lacrimal puncta
- lacrimal canuliculi
- lacrimal sac
- nasolacrimal duct
- nasal cavity inferior to inferior concha
8.
Muscles of the eye movement, actions, functions
lacteral rectus
- action: abduction
2. function: abduction
Muscles of the eye movement, actions, functions:
medial rectus
- adduction
2. adduction
Muscles of the eye movement, actions, functions:
superior rectus
- elevation, adduction, medial rotation
2. elevates abducted eye
Muscles of the eye movement, actions, functions:
inferior rectus
- depression, adduction, lateral rotation
2. depresses abducted eye
Muscles of the eye movement, actions, functions
inferior oblique
- elevation, abduction, lateral rotation
2. elevated adducted eye
Muscles of the eye movement, actions, functions:
superior oblique
- depression, abduction, medial rotation
2. depresses adducted eye
Trochlea and common tendon
- tendon of superior oblique muscle runs through a fibrocartilaginous loop called trochlea and then inserts into the sclera of the eyeball
- 6 ocular muscles move eyeball and four straight and 2 oblique.
- four rectus muscles arise by a common tendinous ring
- look directly upward
- look directly downward
- nerves innervation
- SR&IO
- IR&SO
- LR6 SO4 all others 3
temporal region houses muscles of
mastication
- temporal fossa- superior to zygomatic arch
2. infratemporal fossa- inferior to zygomatic arch
Trigeminal nerve
- innervation
- branches
- lesions
- sensory to face & motor to mm, of mastication
- main sensory nerve to head
- motor nerve for mm. mastication - 3 branches
- to area above and medial to eye (sensory)
- to maxillary region (sensory)
- to mandibular region (sensory & motor) - lesion of trigeminal nerve causes anesthesia of corresponding areas of scalp, face, cornea, conjunctiva, nose, mouth, tongue, and also paralysis of muscles of mastication; when mouth is opened mandible moves to paralyzed side
Temporalis m. OINA
O- floor of temporal fossa
I- coronoid process of mandible
N- CN V
A- anterior & posterior fibers elevate mandible; posterior fibers retract mandible
Masseter m. OINA
O- zygomatic arch
I- lateral surface of mandible
N- CN V
A- elevates and protrudes mandible; deep fibers retrude mandible
medial pterygoid m. OINA
O- tuberosity of maxilla and lateral pterygoid plate
I- medial surface of angle of mandible
N- CN V
A- elevates and helps protrude mandible
Lateral pterygoid m. OINA
O- upper head: greater wing of sphenoid
lower head: lateral pterygoid plate
I- neck of mandible and articualr disc, capsule of TM joint
N- CN V
A- protrude mandible and produce side-side movements
Movement of mandible and TMJ
- temporomandibular joint (TMJ)- formed by head of manduble, mandubular fossa, articualr tubercle of temporal bone
- protraction- lateral, little bit of medial pterygoid, masseter
- retraction- posterior fibers of temporalis, deep part of masseter, geniohyoid, digastric
- elevation- (biting movement) temporalis, masseter, medial pterygoid
- depression- gravity, lateral pterygoid, digastric, geniohyoid, mylohyoid
movement of mandible: lateral (side to side)
- temporal of same side
- lateral pterygoid of opposite side
- medial pterygoid of opposite side
- masseter of same side
TMJ
TMJ- hinge and gliding joing
- 2 movments: forward gliding, hinge-like rotation
- when mouth opened, head and articualr disc move forward until head lies inferior to articular tubercle
- lateral ptyerygoid m. pulls head of mandible anteriorly
- head (condyle) and articular disc slide anteriorly
- occurs only when mouth opens alot
- wear on the bone and/or cartilage can cause pain
- can be confused with ear pain
TMJ dislocation
- easily dislocated
- usually dislocates anteriorly, especially when yawning or taking a large bite
- person is then unable to close mouth
- also dislocated during tooth extraction or by blow to chin when mouth is open (bilaterally)
How TMJ damage occur
- powerful compressive forces act on TMJ
- can occur from:
1. frequently chewing gum
2. frequently chewing hard foods like nuts, hard vegetables, toothpicks
3. grinding teeth
4. nail biting
muscles of mastication: innervated by CN V3
group by actions
- elevates mandible & closes mouth
- temporalis
- masseter
- medial pterygoid - pulls mandible anteriorly & opens mouth
- lateral pterygoid
- anterior belly of digastric - tenses floor & roof of mouth
- mylohyoid
- tensor veli palatini
Palate
- forms roof & floor of nasal cavity
- consists of:
1. hard palate: anterior, immobile
2. soft palate: posterior, mobile, tip is uvula - hard palate is formed by the palatine process of maxillae and horizontal process of palatine bones; it is arched
Muscles of soft palate
- also call velum palatinum
1. tensor veli palatini - tenses soft palate
- opens pharyngotympanic tube
- CN V3
2. levator veli palatini - elevates soft palate
- CN X
3. Uvula- elevates uvula; CN X
4. palatopharyngeus- elevates pharynx; CN X
5. palaglossus- elevates tongue; CN X
extrinsic muscles of tongue
- styloglossus- retracts & elevates tongue; CN XII
- hyoglossus- retracts & depresses tongue; CN XII
- genioglossus- protrudes & depresses tongue; CN XII
- muscles above function: mastication, taste, degluition, articulation, oral cleansing
- hypoglossal n. also supplies intrinsic muscles of tongue
Salivary glands & ducts
- innervated by parasympathetic fibers
- from facial n. CN VII: submandibular gland, sublingual gland
- from glossopharyngeal n. CN IX: paratid gland
