Mandible, TMJ and Muscles of mastication Flashcards
What sort of joint is the TMJ?
A synovial modified hinge joint
What 2 articular processes form the TMJ?
Mandibular fossa of temporal bone
Articular process of the mandible
What movements occur at the mandible?
Opening Closing Protrusion Retrusion Side to side movements
What are the names of the 4 muscles that act on the TMJ during mastication?
Temporalis
Masseter
Medial Pterygoids
Lateral Pterygoids
What are the bony attachments of the temporalis?
Temporal fossa
Coronoid process of the mandible
How do the anterior fibres of the temporalis sit?
Vertically
What action do the posterior fibres have on the mandible when they contract?
Retrusion
What does the master do to the mandible?
Elevates and Protracts
What do both the medial and lateral pterygoid muscles attach to?
Lateral pterygoid plate of the skull
What does the medial pterygoid sit parallel to?
The masseter
Which surface of the lateral pterygoid plate does the medial pterygoid muscle attach to?
Medial surface
When the two lateral pterygoid muscles contract, what do they cause?
Protraction
Depression
When the two medial pterygoid muscles contract, what do they cause?
Elevation
Which 4 supra hyoid muscles cause mandibular depression?
Digastric muscle
Mylohyoid
Stylohyoid
Geniohyoid
Innervation of the muscles of mastication is by what?
Branches of the mandibular division of the trigeminal nerve
