2.2 The Muscles of Masication Flashcards
What are the Muscles of Mastication?
Do not need to name them
A group of muscles which act on the Temporomandibular Joint during masication
Name the 4 Muscles of Mastication:
- Temporalis Muscle
- Masseter Muscle
- Medial Pterygoid Muscle
- Lateral Pterygoid Muscle
What is the Temporalis Muscle?
A large, fan shaped, muscle on the side of the head - covering the Temporal Bone
What are the bony attachments of the Temporalis Muscle?
- Temporal Bone - The floor of the Temporal Fossa, and the Deep surface of the Temproal Fascia
- Coronoid Process - The Tip and the Medial Surface
What are the actions of the anterior fibres of the Temporalis Muscle?
Elevation of the Mandible
What are the actions of the posterior fibres of the Temporalis Muscle?
Retrusion of the Mandible
What are the bony attachments of the Masseter Muscle?
Superior - The Zygomatic Arch (the Maxillary Process of the Zygomatic Bone)
Inferior - The Outer surface of the Ramus, and the Coronoid Process of the Mandible
What are the actions of the Masseter Muscle?
Elevation of the Mandible
What do both the Medial and the Lateral Pterygoid Muscles attach to?
The Lateral Pterygoid Plate of the Sphenoid Bone
What does the Lateral Pterygoid Muscle attach to?
- The Lateral Surface of the Lateral Pterygoid Plate (of the Sphenoid Bone)
- The Infratemporal Surface of the Greater Wing (of the Sphenoid Bone)
- The Neck of the Mandible (After entering into the Temporomandibular Joint)
- Articular Disk of the Temporomandibular Joint
What does the Medial Pterygoid Muscle attach to?
- The Medial Surface of the Lateral Pterygoid Plate (of the Sphenoid Bone)
- The Tuberosity of the Maxilla
- The Medial Surface of the Ramus of the Mandible (Inferior to the Mandibular Foramen)
What happens when the 2 Lateral Pterygoid Muscles contract together?
Protrusion of the Mandible
Depression of the Chin
What happens when the Lateral Pterygoid Muscle contracts with the ipsilateral Medial Pterygoid Muscle?
Swinging of the Mandible to the side of contraction
What happens when the 2 Medial Pterygoid Muscles contract together?
Elevation of the Mandible
What muscles cause depression of the Mandible?
Name the muscles which do:
The Suprahyoid Muscles:
- Mylohyoid
- Geniohyoid
- Digastric (Anterior Belly and Posterior Belly)
- Stylohyoid