Masticating Muscles Flashcards
Masseter: origin (2 heads)
Superficial head: zygomatic arch (anterior 2/3s)
Deep head: zygomatic arch (posterior 1/3)
Masseter: action and insertion
Action: elevates, adducts, and protrudes mandible (chomping down)
Insertion: mandibular angle at masseteric tuberosity
Masseter: vascular and nervous supply
Vascular: masseteric artery
Nervous: Mandibular nerve (branch of CNV3) via the masseteric nerve
Temporalis: action and insertion (2 fiber orientations)
Action:
-vertical fibers: elevate/adduct the mandible
-horizontal fibers: retract/retrude mandible
Unilateral causes lateral movement of mandible to chew
Insertion: coronoid process of mandible (apex and medial surface)
Temporalis: origin
Temporal fossa (inferior temporal line)
Temporalis: vascular and nervous supply
Vascular: deep temporal artery
Nervous: Mandibular nerve (branch of CNV3) via the deep temporal nerves
Lateral pterygoid: action and insertions (2 heads)
Action: bilaterally protrudes mandible, unilaterally moves mandible side to side for chewing
Insertions:
- superior head: TMJ (articular disk)
- inferior head: condylar process of mandible
Lateral pterygoid: origin (2 heads)
Superior head: greater wing of sphenoid (infratemporal crest)
Inferior head: lateral pterygoid plate of sphenoid (LATERAL surface)
Lateral pterygoid: nervous supply
Vascular: maxillary artery (pterygoid branches)
Nervous: Mandibular nerve (branch of CNV3) via lateral pterygoid nerve
Medial pyterygoid: action and insertions (2 heads)
Action: elevates/adducts mandible
Insertion: both superficial and deep head insert at the same place:
Pterygoid tuberosity on medial surface of mandibular angle
Medial pterygoid: origins (2 heads)
Superficial head: maxilla bone (tuberosity)
Deep head: MEDIAL surface of lateral pterygoid plate, pterygoid fossa
Medial pterygoid: vascular and nervous supply
Vascular: maxillary artery (pterygoid branches)
Nervous: mandibular nerve via nerve to medial pterygoid
