Endo (pulp and Perio disease progerssion)

What are the 4 histological zones of the pulp

Odontoblastic, cell-poor, cell-rich, pulp core

What features are in the odontoblastic layer of the pulp

cell bodies of odontoblasts, nerve fibers, capillaries

What part of the pulp contains more odontoblasts

coronal pulp (less in radicular pulp)

What features are in the cell-poor zone

capillaries, unmyelinated nerve fibers, fibroblast processes

What layer of the pulp may be absent when dentin is formed (increased dentin formation)

cell-poor zone

What does the cell-rich zone contain

fibroblasts, macrophages, dendritic cells, undifferentiated mesenchymal stem cells

What does the pulp proper contain

Loose conn. tissue, larger blood vessels, fibroblasts

What is the most prominent cell in the pulp proper

fibroblasts

what types of blood vessels are in the pulp

arterioles, venules, capillaries

Where do the vessels of the tooth enter

apical canal

What type of teeth are more likely to revasularize with trauma

teeth with wide apices

Where does the pulp receive motor innervation from

superior cervical ganglion

The sensory nerves of the pulp arise from the what nerve

trigeminal nerve

What is the complex of nerves in the tooth when they reach the coronal pulp, they fan out beneath the cell-rich zone and branch into smaller bundles known as the parietal layer of nerves

plexus of Raschkow

What is the widely believed pulpal pain conduction theory

hydrodynamic theory

What type of nerve fibers are affected by hydrodynamic stimulation

A-fibers

What type of nerve fibers are affected by inflammatory mediators

C-fibers

What is the function of A-delta fibers?

Pain and temperature

What is the function of C fibers?

Pain

What type of fiber is A-delta?

Myelinated

What type of fiber is C fiber?

Unmyelinated

Where do A-delta fibers terminate?

Pulp-dentin complex

Where do C fibers terminate?

Throughout the pulp

How fast do A-delta fibers conduct impulses?

Fast

How fast do C fibers conduct impulses?

Slower

What is the threshold of A-delta fibers?

Relatively low

What is the threshold of C fibers?

Relatively high, usually associated with tissue injury

What type of pain is associated with A-delta fibers?

Sharp, pricking pain

What type of pain is associated with C fibers?

Dull, ache, less bearable than A-delta fiber sensation

Which dental nerve fibers are myelinated and responsible for sharp, pricking pain?

A-delta fibers

Which dental nerve fibers are unmyelinated and responsible for dull, aching pain?

C fibers

Which fiber has a faster conduction velocity, A-delta or C?

A-delta

Which fiber has a lower threshold, A-delta or C?

A-delta

Which fiber has a higher threshold, A-delta or C?

C fiber

Which fiber is associated with the pulp-dentin complex?

A-delta

Which fiber extends throughout the pulp?

C fiber

Which fiber is associated with pain and temperature sensation?

A-delta

Which fiber is associated with pain sensation only?

C fiber

What are the steps of the inflammatory response

Recognition, Recruitment, Removal, Regulation, Repair (resolution)

What is the typical onset of acute inflammation?

Fast: minutes or hours

What is the typical onset of chronic inflammation?

Slow: days

What is the predominant cellular infiltrate in acute inflammation?

Neutrophils

What is the predominant cellular infiltrate in chronic inflammation?

Monocytes/macrophages and lymphocytes

How does tissue injury and fibrosis typically differ between acute and chronic inflammation?

Acute: usually mild and self-limited; chronic: often severe and progressive

What are the three major features used to distinguish acute from chronic inflammation?

Onset, cellular infiltrate, and tissue injury/fibrosis

How does the cellular infiltrate differ between acute and chronic inflammation?

Acute: neutrophils; chronic: monocytes/macrophages and lymphocytes

How does the onset differ between acute and chronic inflammation?

Acute: minutes or hours; chronic: days

How does tissue injury and fibrosis differ between acute and chronic inflammation?

Acute: usually mild and self-limited; chronic: often severe and progressive

What are the main cells of inflammation

PMN, Macrophage, and lymphocyte

What type of inflammation is characterized by the exudation of fluid and plasma proteins (edema) and the emigration of leukocytes, predominantly neutrophils

acute inflammation

What type of inflammation is associated with more tissue destruction and scarring (fibrosis).

chronic inflammation

What is the process of locomotion along a chemical gradient

chemotaxis

what chemical mediator is released by activated mast cells and acts on venules to cause immediate dilation and ↑ vascular permeability

histamine

What chemical mediator is released when the cell membrane is damaged and causes vasodilation and ↑ vascular permeability

Bradykinin

what chemical mediator is produced from arachidonic acid by COX enzymes as a result of damaged cell membranes

prostaglandin

What are the cardinal sign of inflammation

Rubor (redness), Tumor (swelling), Calor (heat), Dolor (pain)

What are the categories of pulpal irritants

microbial, chemical, mechanical, trauma

at what rate does dental caries progresses through dentin

1/2 - 1 mm per 6 months

a dental irritant is typically mild until it gets how close to the pulp

1 mm

Why is there more microleakage under composite then amalgam

removal of smear layer

What is the first dental response to irritants

sclerotic dentin

What type of dentin is formed during tooth development; organized tubulues

primary dentin

What type of dentin is deposited after tooth maturation; regular tubular pattern

secondary dentin

is there more primary or secondary dentin

primary

what separates the primary and secondary dentin

demarcation zone

what type of dentin is formed by external influences, including caries and attrition

tertiary dentin

what type of dentin forms from mild stimulus from injury to odontoblasts

reactionary dentin

what type of dentin forms from death to odontoblasts

reparative dentin

What growth factor stimulates the growth of reactionary dentin

TNF-B

What cells migrate and differentiate to form new odontoblasts

dendritic cells (from cell rich zone) & undifferentiated mesenchymal cells (from pulp proper)

Rank the dentin tubules from most permeable to bacteria to least permeable

Dead tracts (no ODB), unaffected tubules, deposition of RD, deposition of sclerotic dentin

What is the goal of endodontics

prevent or cure pulpitis and apical periodontitis

What was found in Kakehashi and Stanley study

etiology of apical periodontitis is bacteria

What were the test specimens of Kakehashi and Stanley

germ-free rats and normal rats