dentin

Question 1

features of dentin

Answer 1

harder than nbone, softer than enamel
70%hydroxyapetitite, 20%protein 10%water
living sensitive tissue with blood vessels and nerves

Question 2

dentin can repair itself T/F

Answer 2

T

Question 3

dentin formation begins with the ??

Answer 3

bud stage in the dental paplillae and then cusp debelopment begins which will grow tpward cervical loop

Question 4

Hertwig’s epithelial root sheeth

Answer 4

induces root dentin to form

Question 5

steps of dentinogenesis

Answer 5

1. ameloblast differentiate and signal ectomesenchyme
2. ectomesenchyme poliferate
3. cells in contact with the basal lamina of ameloblast diffrentiate
4. cells elongate
5. RER and golgi enlarge

Question 6

secretion of matrix

Answer 6

nucleus move basally
odontoblast formation begins
cell to cell junction form
basal lamina break down

Question 7

types of collagen during dentogenesisi

Answer 7

type 3 (korff's fibers = secreted first) and form mantle dentin 
collage type 1 fibers secreted next

Question 8

Tomes’ fiber

Answer 8

odontoblastic processes

Question 9

mineralization type for Slow-growing dentin (eg root)

Answer 9

linear mineralization

Question 10

mineralization type for Fast-growing dentin (crown) .

Answer 10

appears to be mineralized in globs (calcospherites)

Question 11

regions of the dentin

Answer 11

• Mantle = outermost; first deposited
• Primary = bulk of circumpulpal dentin
• Secondary = formed after teeth occlude; slowly narrows pulp
• Tertiary (reparative) = results from pulpal stimulation by injury; irregular

Question 12

peritubular dentin

Answer 12

Lining the tubules is a layer of peritubular dentin which is hypermineralized. In some areas it is so thick that it narrows or even occludes the tubule.

Question 13

sclerotic dentin

Answer 13

When tubules have become occluded, will be translucent when placed in water. Occurs in normal physiological aging. Because it reduces permeability, may prolong pulp vitality.

Question 14

interglobular dentin

Answer 14

happens when the globular zones don’t fuse

there are tubules but no peritubular dentin

Question 15

what type of difiency is associated with interglobular ?

Answer 15

vit. D

Question 16

Contour lens of owen

Answer 16

accentuated incremental lines caused by birth or illness

Question 17

dead tracts

Answer 17

loss of odontoblastic processes.. appears dark because it traps air

Question 18

granular layer of tome’s

Answer 18

an external edge of root between the cementum

Question 19

dentin resorption

Answer 19

odontoclast replace odontoblast and tooth becomes oink