Gda Lecture 3 Development Of Mandible/tmj

Front 1

Steps of Development for Mandible

Back 1

1. True Fusion of Mandibular processes(via 1st branchial arch)

2. Meckel's cartilage:induces formation of mandible and serves as scaffolding for formation of mandible

3. 7 weeks, intramembranous ossification of facial bones begins

4.10th week: palatal shelves fused, elevated at the midline, apoptosis eliminate epithelial tissue midline.

-->palatal shelves have ectomesenchyme that needs to be replaced by bone after palatal shelf elevation

5. 12 Week: Development of mandibular condyle of TMJ via appearance of condylar cartilage.
-->condylar cartilage = growth site with, superior via enchondral, inferior via intramembranous

-->Meckels shrinks and forms incus/malleus

Front 2

Distinguish endochondral and intramembranous bone formation?

Back 2

1. Intramembranous ossification: production of bone matrix and ossification within ectomesenchyme.

occurs in the body of the mandible, lateral Meckel's cartilage, in the facial bones and in the inferior condylar process

2. Endochondral Ossification: replacment of cartilage by bone

occurs in superior condylar process, through condrylar cartilage

Front 3

Compare/Contrast TMJ synovial

Back 3

1. articular surfaces condyle, disc, temporal bone covered with Fibrous Connective Tissue

2.articular disc which seperates upper and lower compartnments

3. Hanging and sliding/gliding motion

Synovial have hyaline and no articular disc