dental pulp and caries

Question 1

stages of pulp

Answer 1

embryogensis: same as rest of tooth
begins forming in the cap stage
in the bell stage blood vessels will form

Question 2

dental pulp derived from what kind of cell?

divisions?

Answer 2

The dental pulp consists of loose connective tissue
derived from neural crest (ectomesenchymal) cells.

Mature dental pulp is divided into two compartments

Question 3

compartments of dental pulp

Answer 3

odontoblast layer

pulpal core

Question 4

odontogenic zone laYERS

Answer 4

• Odontoblast cell layer
• Cell-free zone of Weil
• Cell-rich zone
• Parietal plexus of nerves (Raschkow’s plexus)

Question 5

pulpal core contents

Answer 5

• Fibroblasts
• Type I and III collagen
• Extracellular matrix
• Blood vessels
• Nerve tissue

Question 6

odontogenic zone organization

Answer 6

Question 7

functions of pulp

Answer 7

• Embryonic induction
• Formative
• Protective
• Reparative

Question 8

cell populations of pulp

Answer 8

 Odontoblasts
 Fibroblasts MAJORITY OF CELLS
 Undifferentiated mesenchymal cells
 Macrophages AND Dendritic cells= 8% of cell population
 Blood vessel-related cells (e.g., endothelial & pericytes)
 Neural-related cells (e.g., Schwann cells)
 Lymphocytes

Question 9

extracellular matrix of pulp

Answer 9

  Collagen types I, III, IV, and V (via odontoblasts) III MOST ABUNDANT 
  Non-collagenous matrix components: 
•  Proteoglycans 
•  Glycosaminoglycans 
•  Phosphoproteins 
•  Glycoproteins 
•  γ- carboxyglutamate-containing proteins 
  BMP-2, 4, and 7 
  FGF
  EGF
  DMP

Question 10

pulp inn
branching?
function?

Answer 10

Pulpal innervation includes both myelinated and
nonmyelinated nerve axons.

They progressively branch, passing through the subodontoblastic layer as the parietal neural plexus (Rashchow’s plexus), on to the odontoblastic cell layer and some fibers enter into dentinal tubules.

Most nerve endings in pulp are for pain (free nerve
endings as sensory afferents from C-V) with a few
concerned with vasodilatation or constriction.

Question 11

sensory afferents of pulp

Answer 11

Sensory afferents from the Trigeminal (C-V): 
•  Pain 
•  Mechanical (pressure) 
•  Thermal (heat) 
•  Tactile (touch)

Question 12

sympathetics of pulp

from where?

Answer 12

Sympathetic branches from the superior
cervical ganglion are primarily vasomotor
fibers to pulpal blood vessels, concerned
for the most part, with vasoconstriction.

Question 13

majority of pulpal axons

Answer 13

The majority of myelinated pulpal nerve axons are
A-δ (A-delta):
• Fast conducting
• Diameter in range of 1-6 μm

Question 14

minority of nerve fibers in pulp

Answer 14

1% of myelinated nerve fibers are classified as A-β
(A-beta) fibers:
• 6-12 μm diameter

Question 15

nonmyleinated fibers of pulp

Answer 15

Nonmyelinated fibers are designated as “C” fibers and have small diameters, ranging from 0.4 to 1.2 μm

Question 16

AD and C fibers pain

Answer 16

A-δ fibers are associated with sharp, localized pain.

“C” fibers are associated with dull, diffuse pain.

Question 17

NTs identified in pulp, functions?

Answer 17

CGRP/ substance P-Vasodilatation, stimulates fibroblast cell division
Epi and NE- vasconstriction
dopamine- vasoactive/ precursor to epi
endorphins- dampen nociception

Question 18

each fiber of the pulp contributions to?

most branching seen?

Answer 18

Each fiber contributes at least 8 branches to Raschkow’s plexus.

Most terminate in the plexus as free, nonmyelinated nerve endings.

most branching is seen in the pulpal horns, decreased inn in more mineralized tissues

Question 19

distribution of nn axons in intratubular dentin

Answer 19

most seen in lesser mineralized tissue towards to the surface (pulp horns)
less in minerlaized/apical tissues
blood vessels with same pattern

Question 20

blood vessels of pulp

capillaries relative to the odontoblastic layer?

Answer 20

Venules have a diameter of 100 m to 150 m
 Arterioles have a diameter of 50 m to 100 m
 The terminal capillaries anastomose deep to the
odontoblastic layer:

Question 21

capillaires of dental pulp
distribution
kinds of capillaires

Answer 21

Capillary loops are dense in the coronal and pulp horns
and significantly less dense in the radicular pulp
• Continuous and fenestrated capillaries and lymph vessels
are found in pulp

Question 22

cholesterol with aging in pulp

Answer 22

With aging, blood vessels in pulp will exhibit changes such
as cholesterol plaques (atherosclerosis). If progressive
and severe, atherosclerotic plaques can result in pulpal
hypoxia due to vessel strangulation

Question 23

fenestrated capillaires of pulp leakage

contribute to?

Answer 23

fenestrated capillaries leak serum that becomes a component of the so-called “tissue fluid”.

They also contribute to swelling and edema due to significant leakage of serum in states of inflammation.

Question 24

pulpal fibrosis

possible causes

Answer 24

Pulpal fibrosis occurs with increasing age or persistent low-grade injury

e.g., multiple restorations in a single tooth, chronic bruxism, repeated thermal insult, etc.

Question 25

diffuse calcifications

Answer 25

Irregular calcified deposits along collagen fiber bundles or within blood vessels resulting from chronic low-grade inflammation.

Question 26

pulp stones/denticles

kinds?

Answer 26

True pulp stones contain dentinal tubules.

False pulp stones feature concentric layers of
calcified tissue but are void of dentinal tubules.

Question 27

classifications of pulp stones, clinical issue?

Answer 27

classified as either free, attached or
embedded.
no clinical issues unless a root canal is needed

Question 28

abcesses

Answer 28

An abscess is defined as a dense aggregation of
neutrophils and macrophages and other inflammatory
cells within connective tissue undergoing liquefactive
necrosis.

Question 29

prolongment of dental abcesses result

seen on radiograph?

Answer 29

Due to the inability of pulpal tissue to swell, the increasing edema and inflammatory cell infiltration will eventually lead to pulpal necrosis that, in turn, is expressed clinically by persistent pain and periapical
necrosis of the PDL and associated alveolar bone due to migration of material out of the apical foramen

The periapical necrosis is seen on dental radiographs as a radiolucent area associated with the apex of the involved tooth.

Question 30

abcess treatment

followed with?

Answer 30

usually I and D: incision and drain
attempt to remove all affected material before suturing
may then follow with root canal therapy if needed

Question 31

abcess treatment

Answer 31

usually I and D: incision and drain
attempt to remove all affected material before suturing
may then follow with root canal therapy if needed