EX3; Formation of Mandible and TMJ

Question 1

These are the initial appearances of bone tissue in the area where each of the 206 bone organs of the body form

Answer 1

ossification centers

Question 2

How many ossification centers are in the jaw

Answer 2

2 maxillae (each bone)
2 mandible (each half)

Question 3

In which environments do the ossification centers appear

Answer 3

in mesenchyme

on or within a cartilage model

Question 4

What is the development of an ossification center within mesenchyme called

Answer 4

intramembranous bone organ development

Question 5

What is the development of an ossification center on or within a cartilage model called

Answer 5

endochondral bone organ development

Question 6

True or False

The number os ossification centers varies from bone to bone

Answer 6

True

Question 7

What bones have endochondral ossification centers

Answer 7

ulna

femur

Question 8

True or False

A bone will contain either a endochondral or intramembranous bone organ system, not both

Answer 8

False; some bones, such as the temporal bones, have both

mixed ossification centers

Question 9

This is the location of the addition of bone to a bone organ

Answer 9

growth site

Question 10

The periosteum, endostieum, aversion and volkman canals, and the PDL are all examples of what

Answer 10

growth sites

Question 11

No matter what environment bone tissue from in/on, it always forms within what

Answer 11

a highly vascular connective tissue

Question 12

What is another name for the highly vascular connective tissue that the bone tissue forms in

Answer 12

intramembraneous bone tissue

Question 13

When do the 2 maxillary bones and 2 mandibular halves become one

Answer 13

at the end of the first postnatal year

Question 14

True or False

cartilage is the model for bone and later becomes bone

Answer 14

False; it is resorbed, and does not become bone

Question 15

This serves as the temporary skeleton of mandibular processes of branchial arch 1 and as a temporary attachment for muscles

Answer 15

Meckel’s cartilage

Question 16

What two ear ossicles does Meckel’s cartilage become (endochondral ossification)

Answer 16

malleus and incus

Question 17

What two ligaments does Meckel’s cartilage serve as a site for the appearance of (retrogressive changes)

Answer 17

anterior mallelar and sphenomandibular

Question 18

Meckel’s cartilage serves as a temporary anterior lingual plate of the forming what

Answer 18

mandible halves

Question 19

Meckel’s cartilage serves as what at the chin end of the mandibular halves

Answer 19

growth sites

Question 20

Meckel’s cartilage undergoes growth, mineralization, and respiration while serving as anterior whats and replaced as temporary anterior lingual plates by the encroaching bone tissue of the growing mandible halves

Answer 20

growth sites

Question 21

Meckel’s cartialge serve as both ossification centers for what and as growth site of what

Answer 21

ossification center = ear ossicles

growth site = mandibular half

Question 22

In which weeks does the mandible begin development; the appearance of the 2 ossification centers

Answer 22

in the 6th embryonic week

Question 23

Where does the mandible arise from

Answer 23

2 bilateral ossification centers within mesenchymal tissue, lateral to Meckel’s cartilage

Question 24

The ossification centers of the mandible appear in the area of where

Answer 24

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

Question 25

In which direction does the bone of the mandible grow

Answer 25

anterior and posterior from the centers

Question 26

in this direction, the bone incorporates the distal parts of Meckel's cartilages; becoming the temporary lingual plate and a growth site for each mandible half

Answer 26

anterior

Question 27

in this direction, the bone is in the from of an "U" featuring facial and lingual plates, it incorporates an independent piece of hyaline cartilage that become the condylar cartilage (another growth site)

Answer 27

posterior

Question 28

True or False | The condylar cartilage arises from Meckel's cartilage

Answer 28

False; it is independent

Question 29

These appear in the 6th embryonic week within the mesenhyme lateral to Meckel's cartilages in the area of the future mental foramen

Answer 29

bilateral ossification centers

Question 30

The proximal end of Meckel's cartilage serves as the model for what

Answer 30

malleus incus anterior mallelar ligament

Question 31

The middle area of Meckel's cartilage serves as the model for what

Answer 31

sphenomandibular ligament

Question 32

The distal end of Meckel's cartilage serves as the model for what

Answer 32

temporary anterior lingual plate | growth sites of the mandible halves

Question 33

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

Answer 33

joints or articulations

Question 34

This type of joint permits no mobility (fibrous and suture joints); like between maxillary bones

Answer 34

synarthrosis

Question 35

This type of joint permits slight mobility (cartilaginous joint); like pubis symphysis

Answer 35

amphiarthrosis

Question 36

This type of joint permits a variety of movement (synovial joint); like TMJ

Answer 36

diarthrosis

Question 37

This refers to the TMJs dual compartment structure and function

Answer 37

ginglymoarthrodial joint

Question 38

This is a joint that binds a tooth to a bone socket

Answer 38

gomphosis joint

Question 39

What are the three features of most freely movable joint (like the fetal elbow)

Answer 39

one joint cavity incomplete articular disc cartilage articular surfaces

Question 40

What two bones form the TMJ

Answer 40

``` squamous portion of the temporal bone condyloid process (condyle) mandible ```

Question 41

What are the three unique features of the TMJ

Answer 41

complete articular disc two joint cavities soft connecting tissue articulating surfaces

Question 42

In which week would you see blastema or rudiments of TMJ and site of condylar cartilage appearance

Answer 42

week 8

Question 43

When does cavitation of the TMJ appear (articular disc)

Answer 43

third month in utero

Question 44

This is a growth site of the mandible

Answer 44

hyaline cartilage of the condyle

Question 45

Appositional growth occurs between what

Answer 45

articular connective tissue surface and the condylar cartilage

Question 46

The condylar cartilage remains until about the age of what, when it is replaced by compact bone tissue

Answer 46

25

Question 47

The TMJ blastema is where what structures will form

Answer 47

condylar cartilage articular disc two joint cavities soft tissue articular surfaces