Repair and Regeneration

Question 1

Complete restoration of tissue architecture and function is called?

Answer 1

Regeneration (good as new)

Question 2

Restoration of function but altered architecture is called?

Answer 2

Repair (scars)

Question 3

What are the 4 general phases of tissue repair?

Answer 3

1-Hemostasis (Clot formation)
2-Inflammatory (infiltration of immune cells)
3-Reparative phase (proliferative, migration of cells)
4-Wound contraction and scarring

Question 4

Exposure of collagen in sub endothelium to circulating von willebrand factor causing platelet aggregation is typical of what stage of hemostasis? What binds the platelets together?

Answer 4

Primary hemostasis (platelet plug)

fibrinogen anchors platelets together

*Secondary Hemostasis (blood coagulation) happens simultaneously or just after

Question 5

What are the two pathways of Secondary hemostasis?

Answer 5

• Extrinsic (factor VII and tissue factor interaction)

- Intrinsic (initiated by damaged endothelium (collagen exposure))

Question 6

What happens during the reparative/proliferation phase?

Answer 6

epithelial Cells migrate under fibrin clot and proliferate forming new hemidesmosomes and collagen scaffold.

THen fibroblasts proliferate under those filling the defect and forming a scaffold

Angiogenesis also takes place

Question 7

What cells work to draw wound edges together?

Answer 7

Myofibroblasts (increased actin/myosin)

Question 8

Why is there no scar formed in periodontal repair?

Answer 8

Immediate remodeling of collagen by ligament fibroblasts

*important for tooth movement. GF are added or membranes used to encourage ligament reattachment and limit epithelial invasion

Question 9

What are the 3 primary zones (outer to inner) for dental caries?

Answer 9

1-Surface and body (surface zone re-mineralizes, body is primary zone of demineralization)
2-Dark zone (zone of increasing demineralization)
3-Translucent zone (leading edge of caries)

Question 10

Dentin formed between surviving dentin and restorative material preventing micro leakage is called what?

Answer 10

Dentin bridge

Question 11

Many of the steps in secondary hemostasis or blood coagulation need what mineral?

Answer 11

calcium

Question 12

In secondary hemostasis the main point is that _________ converts into _________ which in turn converts _____________ into ________

Answer 12

prothrombin
thrombin
soluble firbrinogen
insoluble fibrin

Question 13

What are the first inflammatory cells on the scene? The second?

Answer 13

neutrophils

then macrophages

Question 14

What is the problem with diseased pulp in tissue repair?

Answer 14

diseased pulp will not send mesenchymal progenitor cells to replace the odontoblasts and stimulate repair

Question 15

Materials whih are designed to drive repair/regeneration through the use of bioactive factors are called what?

Answer 15

bioactive materials