5th class

Question 1

What are the 3 possibilities for growth?

Answer 1

Hypertrophy
Hyperplasia
Secretion of extracellular matrix

Question 2

Increase in the size of individual cells, which is referred to as ________

Answer 2

hypertrophy.

Question 3

Increase in the number of the cells, which is called ________

Answer 3

hyperplasia

Question 4

Increase in the number of the cells, which is called ________

Answer 4

hyperplasia

Question 5

_______ is the process of bone formation by

osteoblasts.

Answer 5

Ossification (osteogenesis)

Question 6

Ossification begins approximately ___ weeks after fertilization
in an embryo.

Answer 6

6 weeks

Question 7

Before 6 weeks when ossification has begun, the embryonic skeleton
consists entirely of ________ and _________

Answer 7

fibrous membranes and hyaline cartilage.

Question 8

The development of bone from:

•Fibrous membranes is called ________

Answer 8

intramembranous ossification.

Question 9

The development of bone from:

•Hyaline cartilage is called ___________

Answer 9

endochondral ossification.

Question 10

________ is the process of bone development from fibrous membranes.
It is the direct deposition of bone on thin layers of connective tissue and is characteristic of the bones on the top of the skull.

Answer 10

Intramembranous ossification

Question 11

What 3 locations are mentioned in the lecture that undergo intramembranous ossification?

Answer 11

Mandible, Maxilla, and Top of skull

Question 12

What is the progression of cell types in intramembranous ossification?

Answer 12

Mesenchyme cells -> Osteoprogenitor cells -> osteoblasts

Question 13

•Endochondral ossification is the process of bone development from
_________

Answer 13

hyaline cartilage.

Question 14

Where does endochondral ossification occur in the body?

Answer 14

Everywhere but the top of skull, Mandible, and maxilla

Question 15

The craniofacial complex can be divided into what 4 areas that grow
rather differently?

Answer 15

Cranial vault
Cranial base
Nasomaxillary complex
Mandible

Question 16

•The bones that cover the upper and outer surface of the brain.

Answer 16

Cranial Vault:

Question 17

•The bony floor under the brain, which also is the dividing line between the
cranium and the face.

Answer 17

Cranial Base:

Question 18

•Made up of the nose, maxilla and associated bones.

Answer 18

Nasomaxillary Complex:

Question 19

Calvaria grows by ______ ossification.

Answer 19

intramembranous ossification

Question 20

What 3 factors are are involved in calvarium growth?

Answer 20

• Suture growth.
• Remodeling/surface apposition. (after 4yrs)
• Brain expansion.

Question 21

Bones of the cranial base are formed initially in

cartilage and are later transformed by _______ ossification to bone.

Answer 21

endochondral

ossification

Question 22

As ossification proceeds, bands of cartilage called ________

remain between the center of ossification.

Answer 22

synchondroses

Question 23

_______ are bands of primary cartilage that persist between

ossification centres.

Answer 23

Synchondrosis

Question 24

Synchodrosis have ____ epiphyseal plates

Answer 24

2-sided

Question 25

How many Synchondroses are there in the cranial base? | What are their names?

Answer 25

3 Inter-sphenoid Spheno-ethomoidal Spheno-occipital

Question 26

When does the inter-sphenoid synchondrosis fuse?

Answer 26

At birth

Question 27

When does the spheno-ethmoidal synchondrosis fuse?

Answer 27

6 yrs

Question 28

When does the Spheno-occipital synchondrosis fuse?

Answer 28

17-20 yrs

Question 29

Postnatal growth occurs in what 2 ways?

Answer 29

At sutures | By surface remodeling

Question 30

By maxilla growing via sutures and surface remodeling, the maxilla moves in what 2 directions relative to the cranium and cranial base?

Answer 30

downward and forward

Question 31

``` As growth of surrounding soft tissues translates the maxilla downward and forward, opening up space at its ______ and ________ sutural attachments, new bone is added on both sides of the sutures. ```

Answer 31

superior and posterior

Question 32

Where does growth occur most in mandible?

Answer 32

Cartilage covering mandibular condyles

Question 33

Is the chin of the mandible a site of significant growth?

Answer 33

No

Question 34

Outside of the chin and condyles, how does the mandible grow in the other areas?

Answer 34

Remodeling/Apposition

Question 35

Where does the growth via hyperplasia, hypertrophy, and endochondral replacement occur in the mandible?

Answer 35

Condyle and posterior surface of ramus

Question 36

Removal of bone from anterior surface and deposition of bone on the posterior surface of ramus make the mandible ______

Answer 36

longer.

Question 37

In relation to the cranial base, the chin of the mandible moves in what 2 directions?

Answer 37

Down and forward

Question 38

In what direction does the mandibular ramus move?

Answer 38

Posteriorly

Question 39

The correct concept is that the mandible is _______ downward and forward and _____ upward and backward in response to this translation, maintaining its contact with the skull.

Answer 39

translated; grows

Question 40

Due to the vast movement of the ramus over time, does the mandible grow more by endochondral replacement or appostion?

Answer 40

Apposition

Question 41

Which synchondrosis is the most important clinically in ortho?

Answer 41

Shpeno-occipital