TMJ Flashcards Preview

Oral Bio Quiz 4 > TMJ > Flashcards

Flashcards in TMJ Deck (30):
1

What are the fibrous joints?

*Very little movement*

-Sutures - Skull

-Tooth socket - Gomphosis

-Syndesmosis - Immovable CT holding bones together (tibia and fibula)

2

What are cartilaginous joints?

*Little movement*

-Primary (Synchondroses) - Bone and cartilage in direct apposition (Sternocostal junction)

-Secondary (Symphyses) - Fibrous tissue internally in the joint

3

What are synovial jts?

Capsule filled with synovial fluid contained w/in a synovial membrane

4

T/F - The TMJ is a synovial jt.

TRUE

5

What is the TMJ specifically?

Synovial sliding-ginglymoid joint

6

General structure of the TMJ?

-Condyle
—Able to rotate and translate in various ways

-Glenoid fossa

-Articular eminence

7

The TMJ synovial capsule is bound to what 2 things?

Condyle

Glenoid fossa

*Articular disc separates the 2

8

What is the extension of the articular capsule?

ARTICULAR DISC

9

Origins of the mandible?

Intramembranous ossification, except for ramus, and associated with Meckel’s cartilage

10

What forms the primary joint?

Meckel’s cartilage forms the malleus and articulates with the incus

This is how a fetus opens it’s mouth

*This is prior to the development of the condyle and temporal bone

11

What is the secondary joint?

Articulation b/t condylar head and glenoid fossa

12

T/F - The TMJ articular surfaces are covered with fibrous CT, NOT hyaline.
-It’s a dense fibrous coating.

-Why is this an issue?

TRUE

Slow healing

13

What is the dense fibrous tissue on the condyle?

Lamina splendens

14

Tell me about the lamina splendens.

Avascular type I collagen w/ fibroblasts

15

Look at picture on slide 10.

Do it

16

What are the 4 mm of mastication?

Masseter

Med pterygoid

Lat pterygoid

Temporalis

17

T/F - The jt capsule is a dense collagneous sac.

TRUE

18

What do the ligaments associated with the TMJ do?

Stabilizes the jt

Restrict mal-movements

19

What are the 3 ligaments to know about the TMJ?

TMJ ligament - Thickened regions that branch out

Sphenomandibular - Connects sphenoid to mandible

Stylomandibular - Connects styloid process to mandible

20

T/F - Articular disk is continuous with the jt capsule.

TRUE

21

What is the articular disc?

Dense fibrous structure
-Collagen fiber network overlaying fibroblast cells

22

T/F - Posteriorly and anteriorly, the disc is thicker, and the condyle rests on the thinner middle section when jaw is closed

TRUE

23

What are the 2 layers of the synovial membrane?

-Subintima

-Intima

24

What is the subintima?

Loose CT
-Elastin and vasculature

25

What is the intima?

Innermost layer with cells

26

What are the cells of the intima?

-A cells
—Resemble MACROPHAGES

-B cells
—Resemble FIBROBLASTS and contribute PROTEINS in synovial fluid

27

What is the synovial fluid?

Basically blood plasma, containing extra proteins and proteoglycans

28

Tell me about the layers of cartilage.

Progenitor cells->chondroblasts (in a proliferative layer) these secrete ECM w/ type II collagen around themselves

->Once entombed, they form hypertrophic chondrocytes
—THESE UNDERGO ENDOCHONDRAL OSSIFICATION

29

T/F - Mandible is formed by intramembranous ossification, but it is fair to say the articular part of the TMJ is formed by endochondral ossification also.

TRUE

30

T/F - B/c of the endochondral ossification at the articular part, then there is potential for remodeling of the joint in the cases of wear and/or pathologies.

TRUE