muscle of the face Flashcards
def of scalp
skin, connective tissue, aponeurosis, loose areolar tissue, pericranium
characteristic of skin
(sweat and sebaceous gland, abundant arterial supply, good venous and lymphatic drainage)
characteristic of CT
(highly vascularized subcutaneous layer, well supplied with nerves)
what is an aponeurosis
(strong tendinous sheet)
function of loose areolar tissus
(sponge-like, allows movement of 1st
3 layers)
function of pericranium
(forms external periosteum of calvaria)
where does muscle of facial expression lie
within the layers of superficial fascia
origin and insertion of muscle of facial expression
Usually originate in fascia or bones of the skull
• Usually insert into the skin
which muscle fo facial expression are the most important
Most important are those surrounding orifices of the
head (eyes, nose, mouth) • Sphincters
• Dilators
action of frontalis
Draws scalp anteriorly, raises eyebrows and wrinkles
skin of forehead horizontally
action of occipitals
Draws scalp posteriorly
action of orbiculares iris
Closes and protrudes lips, compresses lips against teeth and shapes lips during speech
action of zyg major
Draws angle of mouth superiorly and laterally, as in smiling or laughing
action of zyg minor
Elevates upper lip, exposing maxillary teeth
action of elevator anguli oris
Pulls the angle of the mouth upward
action of levator labii sup
Elevates upper lip
action of depressor labii ing
Depresses lower lip
action of depressor anguli iris
Draws angle of mouth laterally and inferiorly as in opening mouth
action of buccinator
Presses cheeks against teeth and lips (whistling, blowing, and sucking), draws corner of mouth laterally and assists in mastication by keeping food btw teeth (and not btw teeth and cheeks)
action of mentalis
Elevates and protrudes lower lip and pulls the skin of the chin up (pouting)
action of rigorous
Draws angle of mouth laterally, as in tenseness
action of platysma
Draws outer part of lower lip inferiorly and posteriorly (pouting), depresses mandible
action of orbiculares ocul
close eyes
action of corrugated
Draws eyebrow inferiorly and wrinkles skin of forehead vertically as in frowning
action of procerus
Wrinkles the skin between the eyebrows
which muscle move the mandible
Masseter
• Temporalis • Medial Pterygoid • Lateral Pterygoid
action of master
Elevate mandible, as in closing mouth, and retracts mandible
temporalis
Elevates and retracts mandible
action of medial pterygoid
ACTION: Elevates and protracts mandible and moves mandible form side to side
action of lateral pteryfois
Protracts mandible, depresses mandible as in opening mouth, and moves mandible from side to side
action of genioglossus
Depresses tongue and thrusts it anteriorly
action of styloglossus
Elevates tongue and draws it posteriorly
action of palatoglossus
Elevates posterior portion of tongue and draws soft palate down on tongue
action of hyoglosses
Depresses tongue and draws down its sides
muscle of the floor of oral cavity
Digastric (CN V, VII) • Stylohyoid (CN VII) • Mylohyoid (CN V) • Geniohyoid (CN XII)
action of digastric
Elevates hyoid bone and depresses mandible, as in opening the mouth
action of stylohyoid
Elevates hyoid bone and draws it posteriorly
action of mylohyoid
Elevates hyoid bone and floor of mouth and depresses mandible
action of geniohyoid
Elevates hyoid bone, draws hyoid bone and tongue anteriorly and depresses mandible
action of SCM
• Acting bilaterally: flex the cervical portion of vertebral column,
extend head, and elevates sternum during forced inspiration
• Acting unilaterally: laterally flex and rotate head to side opposite contracting muscle
extrinsic muscle of larynx
- Omohyoid (C1-C3)
- Sternohyoid (C1-C3)
- Sternothyroid (C1-C3)
- Thyrohyoid (CN XII, C1)
action of omohyoid and sternohyoid
Depresses hyoid bone
action of sternothyroid
Depresses thyroid cartilage of larynx
action of thyrohyoid
Elevates thyroid cartilage and depresses hyoid bone
what is anesthesia
General anesthesia results in total relaxation of the genioglossus, Causes tongue to fall posteriorly, obstructing airway to lungs
