Muscles of Mastication Flashcards
Origin of Masseter (superficial head & deep head)
Origin:
- Superficial Head: anterior 2/3 of the lower boarder of zygomatic arch
- Deep Head: posterior 1/3 and medial surface of the zygomatic arch
- MUSCLE THAT BECOMES ENLARGED IN PATIENTS WHO CLENCH & GRIND **
Insertion of Masseter (superficial head & deep head)
Insertion:
- Superficial Head: angle of the mandible
- Deep Head: upper half of ramus and as high as the coronoid process of the mandible
Movement of Masseter
Movement:
elevation of mandible during jaw closing
Origin of Temporalis
Origin:
temporal fossa
Insertion of Temporalis
Insertion:
coronoid process of mandible
Movement of Temporalis
Movement:
elevation of mandible during jaw closing & retraction of mandible (lower jack backward)
Origin of Medial pterygoid
Origin:
pterygoid fossa of sphenoid bone
Insertion of Medial pterygoid
Insertion:
angle of mandible
Movement of medial pterygoid
Movement:
elevation of mandible during jaw closing
Origin of Laterial pterygoid (superior head & inferior head)
Origin:
- Superior Head: greater wing of sphenoid bone
- Inferior Head: lateral pterygoid plate from sphenoid bone
- MOST LIKELY AFFECTED BY DIRECT TRAUMA TO TMJ **
Insertion of Laterial pterygoid (both heads)
Insertion:
pterygoid fovea of mandible below condyloid process of mandible and intra-articular cartilage (articular disk) of TMJ
Movement of Lateral pterygoid
Movement:
- Inferior Heads: slight depression of mandible during jaw opening
- One muscle: lateral deviation of mandible (shift lower jaw
- Both muscles: protrusion of mandible (lower jaw forward)
All muscles of mastication are innervated by what nerve and blood supply?
all muscles of mastication are innervated by the mandibular division of the 5th cranial or trigeminal nerve (V3), blood supply by the maxillary artery (branch of the external carotid artery)
