Muscles of the Temporomandibular Joints

Question 1

What are the major muscles of mastication?

Answer 1

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

Question 2

What are the lesser muscles of mastication?
The Suprahyoids

Answer 2

1. Digastric
2. Mylohyoid
3. Geniohyoid
4. Stylohyoid

Question 3

What are the lesser muscles of mastication?
The Infrahyoids

Answer 3

1. Sternohyoid
2. Sternothyroid
3. Thyrohyoid
4. Omohyoid

Question 4

What is the origin, insertion and action of Temporarlis?

Answer 4

O : Temporal Fossa
I : Coronoid Process and Ramus of Mandible
A : Elevates the mandible at the TMJ

Question 5

What is the origin, insertion and action of Masseter?

Answer 5

O : Inferior margins of both zygomatic bone, zygomatic arch and temporal bone
I : Angle, Ramus, Coronoid Process of Mandible
A : Elevates the mandible at the TMJ

Question 6

What is the origin, insertion and action of Lateral Pterygoid?

Answer 6

O : Sphenoid Bone
I : Mandible and TMJ
A :
1. Protract the mandible at the TMJ
2. Contralaterally deviates the mandible at the TMJ

Question 7

What is the origin, insertion and action of Medial Pterygoid?

Answer 7

O : Sphenoid Bone
I : Internal surface of the mandible
A :
1. Elevates the mandible at the TMJ
2. Protracts the mandible at the TMJ
3. Contralaterally deviates the mandible at the TMJ