Muscles Of Mustication

Question 1

What are the muscles of Mastication?

Answer 1

1. Temporalis
2. Masseter
3. Lateral Pterygoid
4. Medial Pterygoid

Question 2

Temporalis fibers

Answer 2

Fan Shaped:
Anterior fibers: vertical
Middle fibers: oblique
Posterior fibers: horizontal

Question 3

Temporalis Origin

Answer 3

• Temporal Fossa
• Inferior Temporal Line
• Temporal Fascia

Question 4

Temporalis insertion

Answer 4

1. Tip and medial surface coronoid surface.
2. Anterior border of mandible ramus.

Question 5

Temporalis nerve supply

Answer 5

2 deep temporal nerves coming from the anterior division of mandibular nerve.

Question 6

Temporalis Action

Answer 6

1. Elevation (anterior fibers)
2. Retraction (posterior fibers)

Question 7

Masseter fibers

Answer 7

1. Superficial fibers: oblique.
2. Deep fibers: vertical.

Question 8

Masseter origin

Answer 8

1. Superficial fibers: lower border of zygomatic arch.
2. Deep fibers: deep surface of zygomatic arch.

Question 9

Masseter insertion

Answer 9

Lateral surface of mandible ramus.

Question 10

Masseter nerve supply

Answer 10

Masseteric nerve (anterior division of mandibular nerve)

Question 11

Masseter action

Answer 11

1. Protraction mandible: superficial fibers.
2. Elevation mandible: deep fibers.

Question 12

Lateral Pterygoid origin

Answer 12

1. Upper head:
   Infra-temporal surface and crest of greater wing sphenoid.
2. Lower head:
   Lateral surface of lateral Pterygoid plate.

Question 13

Lateral Pterygoid insertion

Answer 13

1. Pterygoid fovea of mandible neck.
2. Capsule and articular disc of temporomandibular joint.

Question 14

Lateral Pterygoid nerve supply

Answer 14

Nerve to lateral Pterygoid (anterior division of mandibular nerve.

Question 15

Lateral Pterygoid action

Answer 15

1. Depression mandible: lateral Pterygoids both sides.
2. Protraction mandible to opposite side: lateral and medial Pterygoids one side.
3. Side to side movements lateral and medial Pterygoids of both sides alternatively.

Question 16

Medial Pterygoid origin

Answer 16

1. Superficial head: maxillary tuberosity.
2. Deep head: medial surface of lateral Pterygoid plate.

Question 17

Medial Pterygoid insertion

Answer 17

Medial surface of angle and ramus of mandible below mandibular foramen.

Question 18

Medial Pterygoid nerve supply

Answer 18

Nerve to medial Pterygoid (main trunk of mandibular nerve).

Question 19

Medial Pterygoid action

Answer 19

1. Elevation mandible: medial Pterygoids both sides.
2. Protraction mandible to opposite side: lateral and medial Pterygoids one side
3. Side to side movement: lateral and medial Pterygoids of both sides alternatively.