Attachments and Functions of the Muscles of Mastication

What is the action of Temporalis muscle?

Anterior fibers - elevate mandible Posterior fibers - retract mandible

What is the origin and insertion of Temporalis muscle?

O: Floor of temp. fossa I: Coronoid pr. and ant. border of the ramus of mandible

What is the origin and insertion of superior head of lateral pterygoid?

O: infratemporal surface of the gr. wing of sphenoid I: Articular disc (meniscus) of the TMJ

What is the action of the medial pterygoid?

elevates and protracts the jaw

What is the origin of the deep head of medial pterygoid?

medial surface of the lateral pterygoid plate Two heads unite to form common insertion

What are the four muscles of mastication?

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

What is the action of the Masseter muscle?

Elevates mandible

What is the origin and insertion of the inferior head of lateral pterygoid?

O: lateral surface of the lateral pterygoid plate I: pterygoid fovea of the neck of the mandible

What is the origin and insertion of the superficial head of medial pterygoid?

O: maxillary tuberosity I: medial surface of the angle and ramus of the mandible Two heads unite to form common insertion

What is the origin and insertion of Masseter muscle?

O: zygomatic pr. of maxilla and lower border of zygomatic arch I: lateral surfaces of the coronoid pr., ramus and angle of mandible

What is the action of the lateral pterygoid?

Protract and depress the jaw