Chronic Inflammation Flashcards
What follows acute inflammation?
DEMOLITION STAGE: Macrophages engulf fibrin/ red cells/ degenerate PMNL/ bacteria etc to form scavenger function.
What major factors influence the changes which follow the formation of acute inflammatory exudate?
- Amount of tissue damage sustained
2. Whether or not the causative agents remain
What happens after the formation of acute inflammatory exudate, if the causative agent is removed?
- Initial PMNL exudate is replaced by a mononuclear one and demolition stage begins
- If there is no tissue loss, RESOLUTION occurs:
- Cellular damage is slight & reversible
- Organ returns to normal
If there is tissue loss REPAIR & REGENERATION (if tissue is capable of division e.g. in an ulcer) may occur
What happens after the formation of acute inflammation exudate, if the cause of inflammation is not removed?
chronic inflammation occurs (e.g. chronic ginigvitis/ periodontitis) where destruction and healing occur simultaneously. (can be primary=denova)
- decrease in number of polymorphs, lymphocytes & plasma cells
- proliferation of vascular epithelium = capillaries
- proliferation of fibroblasts with collagen production = fibrosis
- granulation tissue forms which is highly vascular & may haemorrhage (one of the reasons why bleeding occurs during chronic gingivitis)
How does granulation tissue form?
proliferation and migration of surrounding connective tissue elements Has: -capillary loops -fibroblasts -inflammatory cells
How does scar tissue form from a chronic inflammatory lesion?
-Fibroblasts lay down collagen (scar tissue)
Why does scar tissue gradually become avascular?
-Lumina of small arteries and arterioles are gradually obliterated by thickening of tunica intima (becomes avascular)
Why does chronic gingivitis have massive plasma cell infiltrate?
Plasma cells produce immunoglobulins ?
