pulpal repsonce to adverse stimulaiton

Question 1

sequence of inflammation

Answer 1

1) painful pulpitis
2) pulp tissue breakdown (pulpal necrosis)
3) root canal infection leading to apical periodontitis/abscess

Question 2

vascular events during extensive inflammation

Answer 2

• vasodilation and increased vascular permeability occurs resulting in exudation
• leading to oedema occurring, leading to an increase in tissue hydrostatic pressure within and around the vessels
• tissue pressure may exceed that of the thin walled venules which collapse
• drainage is impeded and stagnation occurs (lymphatic vessels unable to drain the fluid)
• stagnation increases blood viscosity and impairs removal of waste products
• cell death and tissue necrosis ultimately occur

In response to this

• lymphatic channels attempt to increase absorption
• redistribution of blood flow through AVA shunts (if some of the vessels have collapsed)

Question 3

access development

Answer 3

, polymorphonuclear leukocytes continue to accumulate near the exposed pulp area

• PMNs add to tissue damage by releasing enzymes and oxygen derived radicals that degrade pulp tissue components
• bacterial products such as enzymes, metabolites and leukotoxins also contribute to direct tissue damage
• localised accesses may develop in the most inflamed areas

Question 4

pulp dentine complex componnents

Answer 4

dentine
predentine
odontoblasts
cell free zone
cell rich zone

Question 5

anatomical features of pulp

Answer 5

unyielding walls
constricted blood source
tooth surrounded by bone

Question 6

what extend into dentine tubules

Answer 6

odontoblasts alongside nerve fibres

Question 7

tubular fluid

Answer 7

constant flow away from the pulp

any toxin progressing down tubules will be prevented

Question 8

characteristics of dentine

Answer 8

odontoblast process extents into the tubule and dentine forms around it
positive pressure of fluid from the pulpal end
- A delta nerve fibres extend into the tubules
- C fibres run in the deeper pulpal tissues
- primary odontoblasts lays down primary and secondary dentine

Question 9

hydrodynamic mechanisms of pulp nerve activation and odontoblast damge

Answer 9

stimuli creates fluid movement within the tubules
movement detected by the nerves in odotoblast rea
creates action potential leading to pain

Question 10

faster dentine is formed..

Answer 10

• less sensitive to thermal, osmotic, evaporative stimuli
• more porous and impregnated with soft tissue (therefore prone to infection and become necrotic due to no blood supply)
• reduced or no tubular fluid (fluid is useful for protection in terms of stimuli)
• inflammation can lead to loss of vitality

Question 11

how to reduce microbial contamination during operative procedures

Answer 11

rubber damn
antimicrobial agents (clorhexidine socked onto a cotton wool pledget)