Dentin!

Question 0

Process of making dentin?

Answer 0

1. Collagenous matrix from odontoblasts

2. Maturation through matrix

Question 1

What is the origin of dentin?

Answer 1

Outer cells of dental papilla (ectomesechyme)

Question 2

Dentin anatomy?

Answer 2

70% inorganic-by hydroxyapatite
20% organic-collagen
10% water

Question 3

How is dentin formed?

Answer 3

1. Continues as long as tooth is vital
2. Can be stimulated environmentally
   Ex: cutting dentin away at the dej, or heavy handed scaling

Question 4

Function of dentin?

Answer 4

Shock absorber for the tooth

Question 5

Color of dentin?

Answer 5

Basically yellow

Question 6

Foramina and lateral canals in dentin?

Answer 6

Found in the root.

-apical foramen transmits nervous and circulatory elements

Question 7

Dej in dentin?

Answer 7

Scalloped union with enamel

Increases surface area which increases strength of the union

Question 8

3 different types of dentin

Answer 8

1. Peritubular
2. Intertubular
3. Circumpupal

Question 9

Components of mature dentin?

Answer 9

1. Dentin tubules
   - travel from pulp to dej
   - contain h2o, odontoblastic process and afferent neuron
2. Dentinal permeability-tubules/mm2
3. Odontoblastic processes is a cellular extension
4. Dentinal fluid

Question 10

Peritubular dentin

Answer 10

Creates the walls of dentin tubules

Question 11

Intertubular dentin

Answer 11

Dentin between tubules

Also the least mineralized

Question 12

Circumpulpal dentin

Answer 12

Surrounds the pulp chamber
Most deep
Most mineralized

Question 13

3 dentin types based on formation

Answer 13

1. Primary
2. Secondary
3. Tertiary

Question 14

Primary dentin formation

Answer 14

Formed before closing of the apical foramen

Question 15

Secondary formation of dentin

Answer 15

Deposited at the pulpit periphery after root is completed.

This is the process of odontoblasts laying dentin down which makes pulp look smaller

Question 16

Tertiary formation of dentin

Answer 16

Formed in response to noxious stimuli

Ex. When someone cuts into dentin or stimulates odontoblasts. Can also include dental caries

Question 17

3 types of dentin based on mineralization

Answer 17

1. Globular mineralization
2. Secondary mineralization
3. Inter globular dentin

Question 18

Globular mineralization

Answer 18

Fusion of primary and secondary formation to completion

Question 19

Secondary mineralization

Answer 19

Occurs after primary formation is done. Some areas fuse with primary formation but not all complete

Question 20

Interglobular dentin

Answer 20

Less calcified and less mineralize. More present closer to the DEJ

Question 21

Some microscopic features of dentin

Answer 21

1. Imbrication lines of vonEbner-daily difference in apposition/maturation
2. Contour lines of Owen-from trauma
3. Neonatal line-most obvious; trauma of birth
4. Granular layer of tomes-just deep to cej or CDJ-less calcified