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Flashcards in Pulp Deck (61):
1

Pulp

Soft connective tissue that supports dentin

2

What are some unique features of pulp?

Vascular
Not calcified

3

What is the embryonic origin of the pulp?

Ectoderm - neural crest ectomesenchyme - dental papilla

4

What are some contents of pulp?

Cells and cellular elements
Blood and lymphatic vessels
Extracellular matrix

5

What are the functions of pulp?

Inductive
Formative
Nutritive
Protective
Defensive/Repairative

6

Inductive function of pulp

Very early in development, it is involved in inducing transition from dental lamina to bud stage

7

Nutritive function of pulp

Helps supply the dentin with nutrients and water

8

What changes might an endodontically treated tooth undergo?

Dentin will become more brittle because pulp can bring nutrients

9

What are the protective mechanisms of the pulp?

Sensory mechanism
Barrier

10

Sensory mechanism of pulpal protection

Nerve fibers travel in the pulp, which inform us if the tooth is injured, causing us to use the tooth less, preventing further damage

11

Barrier mechanism of pulpal protection

Pulp are under positive pressure at odontoblast junctions - if there is a break, the positive pressure forces things out into the oral cavity, protecting the underlying pulp

12

Defensive/repairative mechanisms of pulp

Immune system
Formation of new dentin and pulp

13

What are the types of foramina of the pulp?

Apical foramen
Accessory foramen

14

What happens to pulp chambers as we age?

They get smaller - making endo more difficult with older patients
Pulp has more cells at a young age and more extracellular matrix in older ages

15

T/F - the pulp is never calcified

False - it is common to have ectopic calcifications

16

What are the types of ectopic calcifications?

Pulp stones
Diffuse calcifications

17

Pulp stones

Ectopic calcification commonly found in pulp chamber in crown of the tooth
Spherical or ovoid
No clear cause

18

Diffuse calcifications

Ectopic calcification often found near blood vessels

19

Are ectopic calcifications problematic?

Not likely, mostly likely just an annoyance if you're an endodontist

20

What are the zones of the pulp?

Odontogenic zone
Pulp core

21

Odontogenic zone layers

Odontoblast layer
Cell free zone
Cell rich zone

22

Odontoblast layer

Most superficial layer of odontogenic zone
Single layer of odontoblasts lining the pulp dentin border
Can look like multiple layers, but its likely an artifact of how the slide was cut

23

Cell free zone

Cells are less prominent
Middle layer of odontogenic zone

24

Cell rich zone

Increase concentration of fibroblasts
Deep layer of odontogenic zone

25

Pulp core

Lots of fibroblasts, blood vessels, and nerves

26

What cells are found in the pulp?

Odontoblasts
Fibroblats
Immune system cells
Stem cells

27

Odontoblasts

Cells that make dentin
Has processes that go into dentinal tubules

28

Fibroblasts

Confined in the pulp
Secrete ECM of the pulp
-mostly collage, but other proteins as well

29

What are the 2 types of immune system cells in the pulp?

Resident immune cells
Inflammation cells

30

What are the types of Resident Immune cells

Macrophages
Lymphocytes
Eosinophils
Dendritic cells

31

Dendritic cells

Sit at the PD order, surveying the environment
If there's an infection, these present the infection to the immune system

32

Inflammation cells

When you get a tooth infection, these cell numbers increase
Plasma cells
Mast cells
PMNs

33

Stem cells

Source of replacement for odontoblasts or fibroblasts
High capacity of self reneway
Mutlipotent - can generate multiple cell types

34

What are components of the ECM of the pulp?

Proteoglycas
Glycoproteins
Collagen

35

Proteoglycan function in pulp

Gelatinous matrix for diffusion of molecules through the pulp
Help control when and how much collagen is secreted
Water retention - important for keeping pulp moist and keeping positive pressure

36

Glycoprotein function in the pulp

Cell adhesion to the ECM

37

Collagen function in the pulp

Tensile strength

38

What types of collagen are found in the pulp?

I and III

39

Odontoblast function in the pulp

Dentinogenesis
Nutrients to dentin
Immune - can secrete immunity molecules when needed

40

What are the types of junctions between odontoblasts?

Desmosomes and adherens junction
Gap junctions
Tight junctions

41

Desmosomes and adherens junctions

Maintain position and polarity of odontoblasts

42

Gap junctions

Coorinate dentinogenesis - once one odontoblasts decides to make dentin, it signals to neighbors to do the same thing using gap juncitons

43

Tight juncitons

Form a barrier to prevent things from diffusing between odontoblasts
Sits at apical portion of cells

44

Why are the structures of tight junctions so complex?

The more complex they are, the better they are at keeping things out

45

T/F - Tight junctions prevent all things from getting between odontoblasts

False - small things can still potentially get through. Tight junctions are better at preventing large molecules from going through

46

What is the importance of lymphatic tissue in the pulp?

Healing - they drain proteins that accumulate during inflammation

47

Why does the lymphatic tissue have complex anatomy in the pulp?

To overcome challenges associated with encasement in a hard tissue

48

What are the types of nerve fibers in the pulp

A-delta fibers
C fibers
A-beta fibers

49

What happens to innervation during tooth eruption?

Density of innervation increases - it decreases with aging

50

Where do nerve fibers enter the pulp?

Apical foramen

51

How far do nerve fibers extend into the dentin?

We're not sure - but it's likely not all the way to the DEJ

52

Where is the dentin most highly innervated?

In the crown

53

Hydrodrynamic theory of dentinal pain

Air, solids, or cold can create a fluid wave in the dentinal tubule, which stretches the nerve fiber, activating pain

54

Does pain in the pulp follow the Hydrodynamic theory of dentinal pain?

No, just the dentin.

55

What type of pain receptors are associated with the pulp?

TRP receptors

56

TRP receptors

Family of transmembrane receptors for thermal and inflammatory pain in many regions of the body
Activated by many inflammatory mediators

57

Describe the path of pain associated with A fibers

Dental stimuli -->
Hydrodynamic forces -->
A-beta and A-delta fibers -->
Sharp pain

58

Describe the path of pain associated with C fibers

Infection or trauma -->
Inflammation -->
C fibers -->
Dull pain

59

What fibers can be activated by electric pulp and hot/cold testing?

A fibers

60

What do neuropeptides do at central endings?

They have a transmitter funciton
They bind to receptors on brain neurons and produce pain

61

What do neuropeptides do at peripheral endings?

They have a local regulatory function
They bing with receptors on vasculature and local cells and lead to pro-inflammatory response