Muscles of Facial Expression, Muscles of Mastication Flashcards
Levator labii superioris
Origin- frontal process of maxilla
Insertion - skin of upper lip and alar cartilage of nose
Action- elevates the lip and flares the nose
All facial muscles are innervate by terminal branch of facial nerve CN VII
Orbicularis oculi
Origin- Medial plane of Maxilla , lacrimal bone
Insertion- skin around margin of orbit, and tarsal plate
Action- closes eyelid , blinking
Nasalis
Origin- superior part of canine ridge of maxilla
Insertion- nasal cartilages
Action= flares nose by drawing side of one toward nasal septum
Orbicularis oris
Origin= superiorly, median plea of maxilla and inferiorly, mandible
Insertion- mucous membrane of lips
Action= closes and protrudes lips (whistling, sucking, kissing, resists dissension when blowing.
Depressor Anguli oris
Origin= mandible
Insertion- skin at corner of the mouth, blends with orbicularis oris
Action= pulls angle of outs inferiorly and laterally
Platysma
Origin- skin over lower neck and upper lateral thorax
Insertion- mandible for inferior border and skin over lower face, and angle of mouth
Action= depress mandible and tense skin of lower face and neck Action= Depresses and wrinkles skin of lower face and mouth
Buccinator
Origin-Mandible, pterygomandibular raphe, and alveolar processes of maxilla and mandible
Insertion - angle of mouth, orbicularis oris
Action- presses cheek against molar teeth, thereby aiding chewing . Unilateral- draw mouth to one side.
Risorius
Origin- fascia over masseter
Insertion- skin of corner of the mouth
Action- Retract corner of mouth as in grimacing (smiling muscle
Temporalis
Origin- Floor of temporal fossa
Insertion- Coronoid process of mandible
Action- Vertical fibers- Elevates mandible, horizontal fibers- retract mandible, unilateral- lateral movement of mandible (chewing
Innervation- Mandibular nerve (CN v3)
Masseter
Origin- Zygomatic arch, superficial head is aterior 2/3, and deep head posterior 1/3
Insertion- Ramus of mandible and Coronoid process
Action- Elevates and protrudes mandible
Innervation- mandibular nerve CN v3
Lateral pterygoid
Origin- superior head, greater wing of sphenoid bone; inferior head, lateral pterygoid plate
Insertion- superior- articulate disc of TMJoint; inferior- mandible (condylar process
Action- bilateral, protrudes mandible and depress chin; unilateral- side to side movements aka lateral movements of mandible (chewing
Innervate- mandibular division of the trigeminal nerve CN v3
Medial pterygoid
Origin- superficial head, maxilla tuberosity; deep head- medial surface of lateral pterygoid plate and pterygoid fossa
Insertion- pterygoid tuberosity on medial surface of the mandibular angle
Action- Elevates mandible
Innervate- mandibular nerve is medial pterygoid nerve
