TMJ & Meckels cartilage

Question 1

___ ___ is the initial appearance of bone tissue in the area where each of the 206 Bone organs of the body form.

Answer 1

Ossification center

Question 2

How many mandible and maxillae are formed of the 22 adult skull bone organs?

Answer 2

1 mandible and 2 maxillae

Question 3

Where are the two areas that ossification centers appear?

Answer 3

within mesenchyme or on or within a cartilage model

Question 4

If the ossification center appears within mesenchyme, what is it called?

Answer 4

intramembranous bone organ development

Question 5

What is the ossification center called if it appears on or within a cartilage model?

Answer 5

endochondral bone organ development

Question 6

How many ossification centers are found in the mandible and maxillae?

Answer 6

1 mandible = 2 ossification centers (1 for each halve)

2 maxillary bones = 2 ossification centers for each bone

Question 7

Is it possible for some bones to have mixed ossification centers, both intramembraneous and endochondrial ossification centers?

Answer 7

yes

Question 8

Define a growth site.

Answer 8

It is the addition of bone tissue to a bone organ

Question 9

Growth sites for bone tissue formation include the periosteum, endosteium, haversian and volkman canals and the ___ ___.

Answer 9

periodontal ligament (PDL)

Question 10

No matter what environment bone tissue forms in or on, it always forms within a highly ___ connective tissue that is referred to by some as ___ bone tissue.

Answer 10

vascular; intramembranous

Question 11

Where are the paired Meckel Cartilages located?

Answer 11

One in each mandibular process of branchial arch I

Question 12

The paired Meckel’s Cartilages serve as the temporary skeleton of the ___ processes of branchial arch ___.

Answer 12

mandibular; I

Question 13

T/F. Meckel’s Cartilage does not attach muscles that will eventually attach to the mandible.

Answer 13

False, they serve as temporary attachments for muscles that eventually attach to the mandible

Question 14

Each cartilage serves as models for 2 ear ossicles. What are they?

Answer 14

mallelus and incus

Question 15

The meckel’s cartilage serves as a site for what two ligaments?

Answer 15

anterior mallelar and sphenomandibular

Question 16

The Meckel’s cartilage serves as temporary ___ ___ plate of forming mandible halves.

Answer 16

anterior lingual

Question 17

Meckel’s cartilage serves as an enclosed growth site at the ___ end of the mandible halves.

Answer 17

chin

Question 18

Meckel’s cartilage extends from the proximal part of the ___ ear cavity to the distal part of the ___.

Answer 18

inner; chin

Question 19

Meckel’s cartilage serve as both ___ ___ of ear ossicles and as a ___ ___ of each mandible halve.

Answer 19

ossification centers; growth site

Question 20

T/F. The mandible develops as 3 bilateral halves that exist throughout the interuterine period.

Answer 20

False, The mandible develops as 2 bilateral halves that exist throughout the interuterine period.

Question 21

When does the mandible begin to develop?

Answer 21

week 6

Question 22

Where does the mandible arise from?

Answer 22

2 bilateral ossifciation centers witin mesenchymal tissue lateral to Meckel’s cartilages.

Question 23

Where do the ossification centers appear?

Answer 23

in the area where the inferior alveolar nerve branches into the mental and incisive nerves or site of future mental foramina.

Question 24

Anterior bone growth incorporates the ___ parts of Meckel’s cartilage. This part of each cartilage will become the temporary ____ plate and a ___ ___ of each mandible halve.

Answer 24

anterior; lingual; growth site

Question 25

The ___ bone grows in the form of a ‘U’ featuring ___ and lingual plates.

Answer 25

posterior; facial

Question 26

The posterior end of the facial plate incorporates what independentstructure that becomes the ‘condylar cartilage’, another growth site of each mandible half?

Answer 26

hyaline cartilage

Question 27

T/F. Condylar cartilage arises from Meckel’s cartilage.

Answer 27

False, condylar cartilage does NOT arise from Meckel’s cartilage, it’s independent.

Question 28

At the end of the first ___ year, an osseous union occurs between ___ mandibular halves at the ___ or chin site. Here, the mandible becomes 1 of the ___ skull bones.

Answer 28

postnatal; 2; distal; 22

Question 29

Match:

A. Proximal end
B. Middle area
C. Distal end

1. temporary anterior lingual plate
2. malleus
3. anterior mallelar ligament
4. sphenomandibular ligament
5. incus
6. growth sites of the mandible halve

Answer 29

A - 2, 3, 5
B - 4
C- 1, 6

Question 30

What muscle attach to the medial sides of Meckel’s cartilage?

Answer 30

mylohyoid muscle

Question 31

Define a joint or articulation.

Answer 31

the place of union or junction between two or more bones of the skeleton

Question 32

___ permits little or no mobility. Examples include fibrous and suture joints. These can be found between ___ bones, and temporal and parietal bones.

Answer 32

Synarthrosis; maxillary

Question 33

___ permits slight mobility. Examples include ___ joints. This can be found in the pubis symphysis.

Answer 33

Amphiarthrosis; cartilaginous

Question 34

___ permits a variety of movements. An example includes the synovial joints. This can be found in the ___ joint.

Answer 34

Diarthrosis; temporomandibular

Question 35

What joint binds a tooth to a bone socket?

Answer 35

Gomphosis joint

Question 36

Most freely movable joints include one joint ___, an incomplete ___ disc, and a ___ articular surface. These features are true for most freely moveable joints except what?

Answer 36

cavity; articular; cartilage

temporomandibular joint

Question 37

What two bones form the temporomandibular joint?

Answer 37

temporal = squamous portion
mandible = condyloid process (condyle)

Question 38

What are the unique features of the temporomandibular joint?

Answer 38

complete articular disc
two joint cavities
soft connective tissue articulating surface

Question 39

T/F. The blastema or rudiments of TMJ and site of condylar cartilage appear at week 8 of the embryo along with the cavitation.

Answer 39

False, blastema or rudiments of TMJ and site of condylar cartilage appear but NO cavitation in 8 week embryo

Question 40

When does cavitation occur?

Answer 40

third month in utero

Question 41

Appositional growth occurs between the ___ connective tissue surface and the ___ cartilage.

Answer 41

articular; condylar

Question 42

What happens at the lower end of the hyaline cartilage?

Answer 42

the cartilage is mineralized, resorbed and replaced by bone tissue

Question 43

The condylar cartilage remains until about the age of ___ when it is replaced by ___ bone tissue.

Answer 43

25; compact

Question 44

What structure forms cells, tissues, or organs?

Answer 44

the blastema

Question 45

The TMJ blastema forms ___ cartilage, ___ disc, ___ joint cavities, and soft tissue articular surfaces.

Answer 45

condylar; articular; two