TMJ FLASH Flashcards
(26 cards)
Define ossification center.
Initial appearance of bone tissue in the area where each of the 206 bone organs of the body form.
What is intramembranous bone organ development?
When ossification centers appear within mesenchyme
What is endochondral bone organ development?
When ossification centers appear within a cartilage model
Can some bones have both intramembranous and endochondrial ossification centers?
Yes (the temporal bones) it is referred to as having “mixed ossification centers”
What do ALL bone tissues form in?
Within highly vascular connective tissue that is referred to as “intramembranous” bone tissue.
What are the six roles of Meckel’s cartilages?
Temporary skeleton of mandibular processes of branchial arch I; Temporary attachment for muscles ; Each cartilage is a model for 2 ear ossicles (malleus and incus); Site for appearance of 2 ligaments (anterior mallelar and sphenomandibular); Temporary anterior lingual plate of forming mandible halves; Enclosed growth sites at the chin end of the mandible halves
When does osseous union occur between the halves of the mandible?
At the end of the first postnatal year
When does the mandible begin development?
In the 6th embryonic week
Where does the mandible arise?
From 2 bilateral ossification centers within mesenchymal tissue, lateral to meckel’s cartilage
Where do the ossification centers of the mandible appear?
In the area where the inferior alveolar nerve branches into the mental and incisive nerves (site of future mental foramina)
Define synathrosis joints.
Permit little or no mobility (fibroush and sature joints - between maxillary bones)
Define amphiarthrosis joints
Permits slight mobility (cartilaginous joints - pubis symphysis)
Define diarthrosis joints
Permits a variety of movements (synovial joints - temporalmandibular joint)
Gomphosis joint
Joint that binds a tooth to a bone socket
What part of the temporal bone forms the TMJ?
Squamous portion
What part of the mandible forms the TMJ?
Condyloid process
What makes up the articular surface in the TMJ?
Soft connective tissue
What makes up the articular surface in other freely movable joints?
Cartilage articular surfaces
What is the site of condylar cartilage appearance?
Blastema : TMJ
When does the Blastema appear?
8th week IU
When does cavitation occur in the TMJ?
Third month in utero
When do the 2 ossification centers of the mandible appear?
Sixth week IU
When does the blastema of the TMJ appear?
Eighth week IU
When does the cavitation occur withing the TMJ?
Third month IU
