melfi 2 Flashcards
(35 cards)
What is an ossification center
initial appearance of bone tissue in the area of each of the 206 bones in human body (2 mx, 1 mn)
What is an ossification center within mesenchyme called?
intramembranouse bone organ development
What is an ossification center with a cartilage model called?
endochondral bone organ development
How many ossification centers are there for the mandible/what type are they
intramembranous
2 ossification centers (one for each half)
How many ossification centers are there for the maxilla/what type are they
intramembranous
there are 2 maxillary bones
2 centers for each bone
4 total
Where are some places that bone growth can occur? (add bone tissue onto bone organ)
periosteum
endosteum
haversian/volkman canals
PDL
What branchial arch does Meckel’s cartilage come from
one in each mandibular process of arch I
What are the roles of Meckel’s cartilage (6)
- Temporary skeleton of mandibular process
- Temporary attachment for muscles
- Serves as models for malleus and incus
- Site of appearance of anterior malleolar and sphenomandibular ligaments
- Temporary lingual plate of forming mandible halves
- Enclosed growth sites at the chin end of the mandible halves
What ear ossicles does MC serve as a template for
malleus and incus
What ligaments originate at MC
anterior malleolar
sphenomandibular
What does MC serve as an ossification center for? What does it serve as a growth site for?
ossification center for ear ossicles
growth site of each mandible half
What is going on in the enclosed anterior lingual part of MC?
temporary lingual plate of mandible halves
growth site of developing mandible halves
When do the two halves of the mandible join
end of the first post natal year
When does development of the mandible begin
6th embryonic week
Where does development of the mandible arise
2 bilateral ossification centers within mesenchymal tissue, LATERAL to MC
intramembranous
centers are located at site of future mental foramina
How does the mandible grow anterior to the ossification center
bone incorporates distal parts of MC
this incorporated part becomes temporary lingual plate, growth site of each half
How does the mandible grow posterior to the ossification center
bone is in a U shape with facial and lingual plates
posterior end of facial plate incorporates independent piece of hyaline cartilage that becomes the condylar cartilage (forming another growth site for each half)
Does condylar cartilage arise from MC?
NOOO
How many skull bones re there
22
What does the proximal end of MC become
malleus and incus bones
anterior mallelar ligament
What does the middle area of MC become
sphenomandibular ligament
What does the distal end of MC become
temporary lingual plate
growth sites of mandible halves
What area of MC contributes to mandible growth?
the distal part (most anterior, like near the chin)
Are the mandibular ossification centers lateral or medial to MC
lateral
