The Pulp-Dentin Complex

Question 1

Four zones in pulp

Answer 1

-Odontoblast layer
-Cell poor zone of weil
-Cell rich zone
-pulp proper

Question 2

Which layer of pulp produces dentin

Answer 2

Odontoblastic layer

Question 3

Crown and root difference in dentinal tubules

Answer 3

Crown has more dentinal tubule and larger diameter
Root has less dentinal tubules and smaller diameter

Question 4

What is present in cell free zone

Answer 4

Capillaries and unmyelinated nerve fibers passing

Question 5

What happens when odontoblasts die during mechanical injury or caries

Answer 5

Undifferentiated mesenchymal cells from cell rich zone migrate to pulp dentin junction and differentiate into odontoblasts

Question 6

Most numerous cells in pulp

Answer 6

Fibroblasts

Question 7

Most numerous immune cells in pulp

Answer 7

Dendritic cells

Question 8

Cells only found in inflammed pulp

Answer 8

B lymphocytes and mast cells

Question 9

Extracellular matrix of pulp is made of

Answer 9

Glycoproteins
Proteoglycans
Glycosaminoglycans
Amorphous
Gel like
Supports cell

Question 10

During inflammation extracellular matrix is degraded by

Answer 10

Inflammatory mediators and lipopolysaccharides

Question 11

Difference of collagen concentration throughout the pulp

Answer 11

Apical portion of pulp contains more collagen than coronal portion

Question 12

What stage does sensory nerve fibers appear in teeth

Answer 12

Bell stage

Question 13

Which nerve fibers appear first

Answer 13

Unmyelinated C fibers

Question 14

Only sympathetic fibers in pulp

Answer 14

Modulates circulation

Question 15

When pt is having symptoms of reversible pulpitis it is by which nerve fiber

Answer 15

A delta it is present in pulp dentin junction. Cavity doesn’t have to be very deep to feel the pain

Question 16

Irreversible pulpitis is noticed due to which nerve fibers

Answer 16

C fiber present throughout pulp, deep throbbing pain and has relatively deep caries

Question 17

Nerve fibers in pulp are

Answer 17

Nociceptive

Question 18

Pulpal pain is poorly localized because

Answer 18

Pulp does not contain propriocepters and single neuron may innervate more than one tooth

Question 19

What happens to A delta fibers beneath cell rich zone

Answer 19

A delta fibers loose their myelin sheath and divide and form plexus- nerve plexus of Raschkow

Question 20

Why does pt feel pain when lying down if pulp inflammed

Answer 20

Blood flow and pressure increases towards head when pt lies down that causes excessive pressure

Question 21

Main inorganic component of dentin

Answer 21

Calcium hydroxyapatite

Question 22

What type of collagen in dentin

Answer 22

Because it is produced by odontoblasts type I and minor amount of type III

Question 23

What allows for impact of mastication to occur without fracturing enamel

Answer 23

The elasticity of dentin provides flexibility and works as shock absorber

Question 24

Radiopacity of enamel dentin and bone

Answer 24

Enamel>dentin>bone

Question 25

Diameters of dentinal tubule near pulp and at DEJ

Answer 25

Diameter of dentinal tubule is wider near pulp and narrower near DEJ

Question 26

Peritubular dentin

Answer 26

Highly mineralized, less collagen

Question 27

Predentin

Answer 27

First deposited unmineralized dentin, 10 to 50 micrometers and lines at innermost portion

Question 28

Dentin mineralization can occur by which patterns

Answer 28

Globular or linear

Question 29

Which type of calcification is rapid

Answer 29

Globular calcification pattern

Question 30

Globular calcification seen in

Answer 30

Mantle dentin

Question 31

The unmineralized dentin between the mineralized globules is called

Answer 31

Interglobular dentin

Question 32

Which type of calcification is uniform

Answer 32

Linear and slow rate

Question 33

Oldest dentin

Answer 33

Close to enamel/DEJ- mantle or primary dentin, fast rate, globular Newest dentin- closer to pulp, secondary, slower rate, linear- lines of owen

Question 34

Which area of the tooth is very sensitive

Answer 34

Close to DEJ because of profuse branching of dentinal tubules

Question 35

Which dentin forms most of the floor and roof of pulp chamber

Answer 35

Secondary

Question 36

Collagen fibers in dentin

Answer 36

Perpendicular to DEJ

Question 37

2 types of tertiary dentin

Answer 37

Reactionary Reparative

Question 38

Continued deposition of peritubular dentin or mineralization of contents causes

Answer 38

Sclerotic dentin

Question 39

Physiologic and pathologic dentin

Answer 39

Physiologic- primary, secondary, sclerotic Pathologic- teriary

Question 40

Pulp stones more commonly found in

Answer 40

Orifice or within root canal