endodontics

Question 1

goal

Answer 1

1) treatment of periraadicular periodontitis
2) elimination of infected or inflamed tissue

Question 2

what encompasses endodontic treatment

Answer 2

1) non surgical
- vital pulp therapy
- pulp capping and pulpotomy
- RCT
2) surgery

Question 3

vital pulp therapy

Answer 3

1) make sure the pulp that is present remains healthy so PA tissues are also healthy

Question 4

how to decide what treatment

Answer 4

1) status of the pulp
- inflamed or dead
- if inflamed reversible or irreversible
2) history of damage to the pulp?

Question 5

anatomy

Answer 5

1) coronal pulp
2) radicular pulp
3) pulp horns, chamber, canals, apical foramen, lateral accessory canals

mean volume is 0.02 cc
- low compliance environment
- amount of inflammation it can withstand is limited
- pulpal pain is very severe to humankind

Question 6

minor apical diameter

Answer 6

1) where pulp ends
2) stop here with RCT (minor apical diameter)
3) only detect with apex locator

Question 7

anatomy of the dental pulp

Answer 7

1) pulp horn
2) pulp chamber
3) radicular pulp
4) lateral canal
5) CEJ
6) apical foramen

Question 8

histology of the dental pulp

Answer 8

1) organized into 4 zones
- odontoblastic
- subodontoblastic
- cell free
- cell rich
- pulp proper

Question 9

cells of the pulp

Answer 9

1) formative
- odontoblasts and subodontoblasts
2) reparative
- fibroblast, stem cells
3) defense
- macrophage, dendritic, T cells, mast cells

Question 10

odontoblasts

Answer 10

1) form dentin, predentin, matrix
2) active as long as tooth is alive
3) post mitotic cells
- lay some amount of dentin over lifespan (secondary dentin)
4) major damage
- reactionary / tertiary dentin is by subodontoblastic cells
5) also secrete organic content
- collagen, non collagenous protein
- type I most common
- proteins common between dentin and bone
- phosphophoryn specific to dentin
6) also make enzymes

Question 11

hoehl’s cells

Answer 11

1) vital pulp must be present for dentin formation
- aka blood flow

Question 12

odontoblast structure clinical relevant

Answer 12

1) most odontoblastic processes terminate in DEJ
2)dentin and pulp form one structural unit (dentin pulp complex)
3) odontoblast bodies are in close proximity (tight junction)
4) permeability of dentin will be increased making it easily for noxious stimuli to enter
- hydrodynamic effects (ex. extreme cold sensitivity)

Question 13

dentin pulp complex

Answer 13

1) strong functional association

Question 14

microbes or toxins enter the pulp

Answer 14

1) endotoxin and exotoxin
2) if caries goes into dentin, do a pulp test and make sure the pulp is healthy before restoration
3) dentin forming repair and immune mechanisms

Question 15

stromal fibroblasts

Answer 15

1) fibroblasts and stem cells cause repair
2) most prevalent type of cell in the pulp organ
3) role in wound healing and pulp repair in regeneration
- collagen and noncollegenous protein
4) dental pulp stem cells
- mesenchymal cells
- differentiate into preferred cell type
- ex. nerve, fat, bone, etc.

Question 16

macrophages

Answer 16

1) defense response and recognizes irritant
- pro inflammatory environment
2) phagocytose foreign bodies
3) in skin infections, bacteria enter macrophages and can escape phagocytosis
- treatment failure

Question 17

dendritic cells, lymphocytes, mast

Answer 17

1) T immunity
2) mast cell are typical in chronic inflammation
- only see in this kind of pulp
- hemorrhage a lot
- heparin is anticoagulant produced by the mast cell
- more bleeding

Question 18

ECM

Answer 18

1)collagen
2) glycosaminoglycans
- proteoglycans, hyaluronan
3) prevent spread of inflammation
- localizes it to zone
4) can be degraded by MMP

Question 19

collagen

Answer 19

1) primary component of pulp tissue
1) type I and III 26-32% dry weight
2) type i from odontoblasts, III from fibroblasts
3) large and tight bundles toward apical third of root canals

Question 20

von korff

Answer 20

1)extend from odontoblasts into dentin matrix
- type III

Question 21

clinical relevance

Answer 21

1) pulp has largely protein constituents
2) dissolve pulp during RCT
- high PH
2) non specific proteolytic agents (sodium hypochorite)
- dentin also has collagen
3) pulp preservation
- vital pulp therapy
- using bioactive materials that stimulate pulp cells
- dentin formation

Question 22

pulp vitality vs pulp sensibility

Answer 22

we measure sensibility

Question 23

afferent neurons

Answer 23

1) sensory impulses
- thermal, mechanical, chemical ,electric
2) perceive all as pain

Question 24

efferent autonomic neurons

Answer 24

1) modulating microcirculation, inflammation, etc

Question 25

sensory nerve fibers

Answer 25

1) a fibers - myelinated nociceptor - 90% Adelta, Abeta - sharp rapid pain - larger diameter 2) C fibers - unmyelinated - burning, aching - smaller diameter

Question 26

a delta

Answer 26

1) pain, temp, touch 2) stimualted during dentinal tubule movement

Question 27

a beta

Answer 27

1) pressure, touch 2) stimulated during dentinal tubule movement

Question 28

if you cut a cavity without anesthesia, which is stimulated?

Answer 28

1) both a delta and a beta - respond to pressure, touch, pain

Question 29

complaining on drinking cold drinks

Answer 29

1) a delta - temperature

Question 30

spontaneous, severe and unbearable pain

Answer 30

1) C fibers - burning, aching, less bearable 2) pulp has poor repair - need RCT

Question 31

cutting cavity without water coolant

Answer 31

a delta (heat), a beta

Question 32

plexus of raschkow

Answer 32

1) A fibers emerge from schwann cells and branch repeatedly 2) dentin - devoid of sensory nerve fibers (except dentinal tubules)

Question 33

pulp microvasculature

Answer 33

1) pulp vitality = blood supply 2) high blood flow (40-50 ml/min/100 g pulp tissue) > other oral tissues and skeletal muscle

Question 34

pulp microvasculature clinical implications

Answer 34

1) any increase in tissue pressure will cause pain 2) firm and resilient CT limits inflammation to a zone - until it reaches a threshold 3) lack of true collateral blood supply - healing capabilities is less than other organs 4) easy spread of infection from apical foramen into PA tissues 5) vascularity decreases with age

Question 35

neural - vascular connection

Answer 35

1) neuropeptides - CGRP (inflammation and wound healing) - substance P - neurokinin A

Question 36

neural-vascular connection clinical relevance

Answer 36

1) decreases neuropeptide production directly with LA - less pain 2) indirect action with vasoconstriction

Question 37

blood flow for inflamed pulp

Answer 37

1) lying down can cause severe pain (inflamed pulp) - irreversible pulpitis 2) increase in peripheral blood flow, intrapulpal pressure