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BDS1 - Pathology > healing & repair > Flashcards

Flashcards in healing & repair Deck (23)
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1
Q

what are the 4 stages of healing in soft tissues

A

clotting phase
inflammation phase
proliferative phase
maturation phase

2
Q

what type of repair occurs in hard tissues

A

fracture repair

3
Q

regeneration

A

replacement with functional, differentiated cells

4
Q

repair

A

production of a fibrous scar alongside changes in tissue structure/ architecture

5
Q

labile cells

A

continuously dividing and regenerating e.g oral keratinocytes of squamous epithelium of the skin

6
Q

stable cells

A

low levels of replication, rapid proliferation in response to injury, e.g oral fibroblasts

7
Q

permanent cells

A

unable to divide or regenerate e.g neurons

8
Q

what occurs during the clotting phase (haemostasis) of healing

A

clot formation via the coagulation system

mitosis of labile and stable cells

9
Q

what occurs during the inflammation stage of healing

A

innate immune response - macrophages, nuetrophils phagocytose and degrade infectious agents
stimulation of certain cells e.g keratinocytes to to start regeneration or repair

10
Q

granulation tissue

A

new connective tissue with microscopic blood vessels

11
Q

angiogenesis

A

formation of new blood vessels

12
Q

describe how granulation tissue is formed

A

1st phase - vascular granulation tissue - mix of proliferating capillaries, immune cells and fibroblasts. Capillaries are leaky so fluid and cells can enter the tissue
2nd phase - fibrous granulation tissue - capillaries regress and immune cells return to blood, fibroblasts lay down collagen

13
Q

describe the process of angiogenesis

A

new blood vessels are formed from existing vascalature either by sprouting or intussusceptive (splitting). process is driven by VEGF (vascular endothelial growth factor)

14
Q

what occurs during the proliferative stage of healing

A

granulation tissue forms, angiogenesis

15
Q

what is the role of macrophages during the proliferative stage of healing

A

M2 macrophages are essential in the healing and repair process. They engulf/ degrade pathogens and also produce growth factors e.g VEGF and TGFbeta

16
Q

what occurs during the maturation stage of healing

A

granulation tissue is rearranged and collagen fibres are linked

17
Q

primary intention

A

tissue regenerates itself, minimal damage

18
Q

second intention

A

large infected/ damaged area , larger amount of granulation tissue therefore more scar tissue present

19
Q

what are the 4 stages of fracture healing

A

inflammatory stage
repairing stage 1
repairing stage 2
remodelling stage

20
Q

what occurs during the inflammatory stage of fracture healing

A

heamatoma formation at fracture (blood clot within tissue)
immune response to clear debris and dying tissue
bone cells deprived of O2/ blood supply die off
occurs within days

21
Q

what occurs during the 1st repairing stage of fracture healing

A

occurs within weeks
granulation tissue forms and becomes fibrocartilage callus (soft callus)
osteoblasts produce spongy bone

22
Q

what occurs during the 2nd repairing stage of fracture healing

A

occurs within months
remaining granulation tissue is ossified (turned to bone)
formation of hard bone callus
chondrocytes and osteoblasts produce cartilage and bone

23
Q

what occurs during the remodelling stage of fracture healing

A

occurs over months/ years depending on severity
angiogenesis
osteoclasts and blasts remodel the hard callus (resorption and formation)