OCB02-1019 Structure of cementum and alveolar bone

Question 1

What are the functions of the alveolar bone process?

Answer 1

Necessary for muscle attachment
Contains bone marrow for haematopoiesis
It has storage functions for calcium and phosphate ions
Plasticity and remodelling

Question 2

What does the growth of the alveolar bone depend on?

Answer 2

Tooth eruption and root formation

Question 3

What does the alveolar bone rely to for maintenance?

Answer 3

tooth retention because if a tooth is lost, that part of the bone will resorb

Question 4

When does the alveolar bone initially develop?

Answer 4

In the second month of fatal life

Question 5

What are the two kinds of bone in alveolar bone?

Answer 5

Compact and trabecular

Question 6

Which bone has a higher surface area to mass ratio?

Answer 6

Trabecular

Question 7

What is the purpose of compact bone?

Answer 7

Give attachment to the fibres of the periodontal ligament

Question 8

What is bundle bone?

Answer 8

Another term for compact bone due to the bundles of fibres attaching from the periodontal ligament

Question 9

What fibres of the periodontal ligament are embedded in the bundle bone?

Answer 9

Sharpey’s fibres

Question 10

What are the arrangement of sharpey’s fibres?

Answer 10

They are perpendicular to the bone

Question 11

What is lamina dura?

Answer 11

On the radiograph , the bundle bone is more radio dense as the thick bone is seen without trabeculations

Question 12

What is the cribriform plate?

Answer 12

An opening in the alveolar bone which is perforated by blood vessels and nerve

Question 13

What are the names of the 2 septums within the alveolar bone?

Answer 13

Interradicular septum

Interdental septum

Question 14

What is interradicular septum?

Answer 14

Separates the individual roots of a multi rooted tooth

Question 15

What is interdental septum?

Answer 15

Separates two individual teeth

Question 16

What is the blood supply to the alveolar bone?

Answer 16

Periodontal
Alveolar
Supraperiostal/ mucogingival

Question 17

What is the nerve supply to the alveolar bone

Answer 17

Mesencephalic sensory neurons of the trigeminal nerve
Motor nucleus of the trigeminal
Sensory nucleus of the trigeminal
Spinal sensory trigeminal

Question 18

What is type I trabecular bone?

Answer 18

the trabecular are regular and horizontal

Question 19

What is trabecular bone most commonly found?

Answer 19

Mandible

Question 20

What is type II trabecular bone?

Answer 20

irregularly arranged and numerous trabeculae

Question 21

Where is type II trabecular bone found?

Answer 21

Maxilla

Question 22

Where is trabecular bone the most dense?

Answer 22

most dense next to the teeth where it forms the cribriform plate

Question 23

How does tooth loss affect the alveolar bone?

Answer 23

It degrades the bone

Question 24

What is a resting line?

Answer 24

When bone deposition is halted then resumed

Question 25

What is a reversal line?

Answer 25

Resorption by osteoclasts

Question 26

What is cementum?

Answer 26

Bonelike tissue that covers the root of your teeth

Question 27

What cells make cementum?

Answer 27

cementoblasts

Question 28

What are the functions of cementoblasts?

Answer 28

It joins the enamel at the cervix of the tooth creating a cement-enamel junction Cementum attaches the teeth to the alveolar bone by anchoring the PDL Cementum anchors the gingival and periodontal fibres Protects dentin

Question 29

What are the 3 possible origins of cementum?

Answer 29

Pulp cells HERS cells Dental follicle cells

Question 30

What is the composition of cementum?

Answer 30

65% inorganic material: hydroxyapatite 23% organic collagen 12% water

Question 31

What nerve and blood supply does cementum have?

Answer 31

It is avascular and no nerve supply

Question 32

What is a difference between bone and cementum?

Answer 32

Unlike bone, cementum doesn't remodel

Question 33

What is a comparison of minerals of enamel, dentine, cementum and bone?

Answer 33

Enamel 95% Dentine 70% Cementum 65% Bone 60%

Question 34

What is acellular cementum?

Answer 34

It doesn't have any cells in its matrix its rate of deposition is slow Incremental lines are close precementum layer is thin

Question 35

What is cellular cementum?

Answer 35

Contain cementocytes within the matrix The rate of deposition is fast Incremental lines are far apart The precementum layer is thick

Question 36

What do cementocytes occupy?

Answer 36

lacunae

Question 37

What are the channels for cementocytes called?

Answer 37

Canaliculi

Question 38

What is extrinsic fibre cementum?

Answer 38

Fibres such as Sharpey's fibres from the PDL perpendicular to cementum

Question 39

What are intrinsic fibre cementum?

Answer 39

Fibres produced by cementoblasts They are parallel to cementum surface They are found at sites undergoing repair

Question 40

What is mixed fibre cementum?

Answer 40

Mixture of intrinsic and extrinsic fibre cementum