TMJ and muscles of mastication Flashcards
what type of joint is the TMJ?
modified hinge synovial joint
what type of cartilage covers the articular surfaces of the TMJ?
fibrocartilage
what ligaments are involved in the TMJ?
2 extrinsic =
- sphenomandibular
- stylomandibular
1 intrinsic =
- lateral ligament
what are the 5 movements that the TMJ permits?
- protrusion
- retraction
- elevation
- depression
- lateral movements
what pharyngeal arch do the muscles of mastication derive from?
first pharyngeal arch
what are the muscles of mastication innervated by?
CNV
where does the temporalis muscle originate from?
temporal fossa & fascia
where does the temporalis muscle insert into?
coronoid process of mandible & anterior border of ramus
what is the function of the temporalis muscle?
retracts & elevates the mandible
what is the temporalis muscle innervated by?
deep temporal nerves from CNV3
where does the masseter muscle originate from?
maxillary process of zygomatic bone & anterior 2/3rd of inferior border of zygomatic arch
where does the masseter muscle insert into?
angle & lateral surface of ramus of mandible
what is the function of the masseter muscle?
elevates the mandible
what is the masseter innervated by?
masseteric nerve from CNV3
where does the medial pterygoid originate from?
medial surface of lateral pterygoid & maxillary tuberosity & pyramidal process of palatine bone
where does the medial pterygoid insert into?
medial surface of the ramus & angle of mandible
what is the function of the medial pterygoid?
- elevates mandible
- assists with lateral movements
what nerve innervates the medial pterygoid?
nerve to medial pterygoid from CNV3
where does the lateral pterygoid originate from?
infratemporal surface of greater wing of sphenoid bone & lateral surface of lateral pterygoid plate
where does the lateral pterygoid muscle insert?
front of the neck of the mandible
what is the function of the lateral pterygoid?
protrudes the mandible
- assists with lateral and depression movements too
