Muscles Flashcards
Quadrilateral muscles
Originates along the entire lower margin of the eye socket
Runs downward to upper lip
Composed of 3 heads
Quadratus Labii Superioris
3 heads of the Quadratus Labii Superioris
Levator Labii superioris Alaeque Nasi
Levator Labii Superioris
Zygomaticus Minor
Common elevator of the upper lip and wing of the nose
Levator Labii Superioris Alaeque Nasi
Raises the upper lip
Levator Labii Superioris
From the anterior part of the zygomatic bone, it moves obliquely downward and medially inserting in the upper lip at the angle of the mouth
Zygomaticus Minor
Contraction of these two muscles lends to the increasing development of the fold of the skin at the anterior margin of the cheek known as the nasolabial fold
Quadratus Labii Superioris and Levator Anguli Oris
Elevator of the angle of the mouth
Located in the region of the canine teeth
Originates from the canine fossa and inserts into the angle of the mouth
Contributes to the formation of the nasolabial fold and angulus oris eminence
Levator Anguli Oris
Descends obliquely from the posterior portion of the cheekbone to the angle of the mouth
Laughing muscle, draws the angle of the mouth backward and upward
Helps create the nasolabial fold
Points of insertion contributes to the fullness of the angulus oris eminence
Change of planes from the front to the side of the face
Zygomaticus Major
Trumpeter’s muscle
Thin quadrilateral muscle
Principal cheek muscle
Creates the lateral wall of the mouth
Buccinator
Narrow superficial muscle
Origin is the fascia over the masseter muscle
Runs along the cheek area entering the skin at the angle of the mouth
Contraction retracts the angle of the mouth
Antagonistic to the buccinator
Risorius
Three sided muscle
Approaches mouth from below
Originates an oblique line of mandible
Muscle narrows to a small fasciculus and inserts at the angle of the mouth
Contraction depresses the angle of the mouth
Contributes to the prominence of the angulus oris eminence
Depressor Angulus Oris
Small quadrilateral muscle
Approaches lower lip from below
Originates on oblique line of mandible
Moves upward and medially inserting into the skin of the lower lip
Pulls lower lip down and slightly to the side
Will change the form of the line of closure of the mouth
Gives the angulus oris sulcus an oblique form
Depressor Labii Inferioris
Wrinkles the chin
Raises and protrudes the lower lip
Does not insert into the lower lip
Originates at the incisive fossa of the mandible while moving downward to insert into the skin of the chin
May drop fibers into the skin holding it down to form a dimple
Mentalis
Softens the contourof the neck
Lowers the angle of the mandible
Is responsible for the transverse wrinkles of the neck
Platysma
Together they are used to measure the widest part of the neck
Arise from the sternum and the clavicle
Insert into the lateral surface of the mastoid process
Sternocleidomastoid