Lecture # 13: Pulp inflammation & Endo Microbiolgy Flashcards
What is Pulpitis?
- Bacterial infection of dental pulp tissue which results in inflammation of the pulp
- Other reasons: physical trauma, dental instrumentation, and irritating restorative material used by dentists
Like any other living tissue, dental pulp will respond to what?
microbial, mechanical, and chemical insults with the inflammatory process
What are some of the unique characteristics that modify the pulp inflammation process?
1) Anatomical limitations of the hard, root-canal walls that prevent an increase in tissue volume caused by edema (swelling)
Since pulp tissues doesn’t expand during acute inflammation, a rise in internal pulp pressure caused by edema would result in what?
-what is the strangulation theory?
-Pain and also impair the circulation within the pulp and lead to “Strangulation Theory “
Describe the collateral circulation of the pulp
The circulation is very POOR or nonexistent; So if a vessel is occluded or injury or insult the cells fed by the vessel will very quickly DIE and NECROSIS sets in
What is the most common way for plaque to enter the coot canal?
1) Via deep carious lesions
2) Leaky restorations
3) perio infections progressing down the perio ligament thru the apical foremen.
4) enamel cracks/breaks gains access to the dentin tubules and then to the pulp
5) Rarely bacteria may enter a pulp chamber though the blood stream (more common among viruses)
What is the current view of dental pulp reaction to most insults?
1) Local inflammation in the area subjected to the insult
2) If the insult is mild, inflammation may remain local for years
3) If the insult is removed, local inflammation may HEAL
4) If insult is long-lasting and strong inflammation will encompass a greater part of the pulp
5) Process progresses slowly from the periphery where the insult reached the pulp, toward the central pulp, the root pulp and into periapical tissues
6) Successive necrosis of the pulp progresses in the same pattern
Inflammation of the dental pulp is the same as other tissues. What is the steps?
1) Insult/injury/infection direct or indirect via mast cells causes vascular changes typical of inflammation
(Increase BF [smaller than inmost tissues] dilation of capillaries, increased permeability of capillaries = edema)
2) Neuts are 1st Leukocyte to infiltrate pulp and are characteristic fo acute inflammatory process.
3) If insult not removed chronic inflammation develops and characterized by infiltration by monnuclear cells (macro, T cells, and plasma cells)
4) PMNs in acute and Macro’s in CHRONIC have the major task of removing insult. (But they can also cause damage to pulp tissues)
5) If insult not removed, accumulated damage (from insult and inflammatory processes) will cause Pulp tissue delath and necrosis
How was the importance of bacterial infections as an etiological factor of pulpitis shown?
Experiments using germ-free animals where the pulp was exposed yet pulpitis DID NOT develop as it always did in conventional animals
When caries reach the dentin, dentin tubules can act as conduits into pulp for bacteria even before plaque bacteria have _________
infected the pulp
Inflammation (usually chronic-> Mononuclear inflammatory cells; Mac’s T & B cells) & Creation of reactionary or reparative dentin will occur in response to what?
-Response to bacterial products that have diffused down the tubules
- This buys time before the pulp becomes infected.
- Intervention to remove carious lesions and placing a restoration can save the tooth
In carious teeth once plaque bacteria reach the pulp what happens?
irreversible inflammation( acute inflammatory cells: PMNs) almost always sets in
Dental pulp infections are almost always _______ infections. (include which microbes?)
- Polymicrobial
- Normal plaque microflora mainly subgingival, GRAM (-), facultative and ANAEROBIC Microbes dominate.
At least _____ of subgingival gram (-) spp are uncultivable
50%
Which bacteria re commonly associated with Pulpitis?
Gram (+) cocci:
Enterococcus, Step
Gram (-) rods:
Lactobacillus
Actinomyces
Lactobacillus
Gram (-) cocci:
Veillonella
Gram (-) rods: Fusobacterium Porphyromonas Prevotella Tannerella Treponema
