Everything related to Muscles of mastication is explained. From the origin , insertion , nerve supply and the action of muscle . In addition to the images explain .
3. 1
Temporalis
Muscle
Origin
Insertion
Nerve Supply
Action
• Temporal fossa.
• Temporal fascia covers muscle.
• Coronoid process of mandible.
• Two branches of anterior
division of mandibular
nerve .
• Elevation of mandible by
anterior vertical muscle
• Retraction of mandible by
posterior horizontal muscle
fibers .
4. 2
Masseter
muscle
Origin
Insertion
Nerve Supply
Action
• Zygomatic arch
• Lower border of inner surface
of zygomatic arch.
• Outer surface of ramus of
mandible (Lateral) .
• Anterior division of
mandibular nerve .
• Elevation of mandible .
• Protraction of mandible by
its superficial oblique fibers.
• Not considered of content of
infratemporal fossa .
5. 3 Lateral
pterygoid
muscle
Origin
Insertion
Nerve Supply
Action
• Upper head of infra-temporal surface of
greater wing of sphenoid .
• Lower head of lateral surface of lateral
pterygoid plate .
• Pterygoid fovea in front of the neck of
mandible .
• Capsule of TMJ .
• Articular disc of TMJ .
• Anterior division
of mandibular nerve
• Protrusion of mandible
• Opening mouth
• Side to side movement with medial pterygoid .
6. 4 Medial
pterygoid
muscle
Origin
Insertion
Nerve Supply
Action
• Superficial head from maxillary
tuberosity.
• Deep head from medial surface of lateral
pterygoid plate.
• Inner surface of the angle
of mandible (Medial
surface).
• Branch from trunk of
mandibular nerve.
• Elevation & Protrusion of mandible .
• Side to side movement with lateral
pterygoid.
