Muscles of Mastication

Question 1

Temporalis

Answer 1

O : Entire temporal fossa and fascia
I : Anterior border, apex, posterior border, internal surface of coronoid process of the mandible and anterior border of the ramus
A :
1. Elevates the mandible at TMJs
2. Retracts mandible

Question 2

Masseter

Answer 2

O (Superficial Layer) : Inferior margins of the zygomatic bone and the zygomatic arch
I (Superficial Layer) : Angle and inferior 1/2 of external surface of the ramus of mandible
O (Deep Layer) : Inferior margin and deep surface of the zygomatic bone
I (Deep Layer) : External surface of coronoid process of mandible and superior 1/2 of external surface of ramus of mandible
A : Elevate the mandible and assist to protract mandible

Question 3

Medial Pterygoid

Answer 3

O (Deep Head) : Medial surface of the lateral pterygoid plate of the pterygoid process of the sphenoid, the palatine bone and the tuberosity of the maxilla
O (Superficial Head) : Palatine bone and the maxilla
I : Internal surface of the angle and inferior border of the mandible
A :
1. Elevates the mandible at TMJ
2. Protract the mandible at TMJ
3. Contralaterally deviate the mandible at TMJ

Question 4

Lateral Pterygoid

Answer 4

O (Superior Head) : Greater wing of the sphenoid bone
O (Inferior Head) : Lateral surface of the lateral pterygoid of the lateral pterygoid plate of the pterygoid process of the sphenoid
I : Aritcular disc and capsule of TMJ, and neck of mandible
A :
1. Protracts the mandible at TMJ
2. Contralaterally deviates the mandible at TMJ