Pathogenesis

Question 1

Give 3 histological description of a healthy gingiva

Answer 1

Very little plaque accumulation, normal JE, minimal sulcus depth
Few PMN transmigration in JE
Dense collagenous fibers and intact fibroblast

Question 2

List 3 irritants that will cause gingival inflammation

Answer 2

endotoxin, butyric and proprionic acids

Question 3

Give 3 histological description of early gingivitis

Answer 3

Heavy plaque accumulation
PMN transmigrate the JE and palisade against bacteria
In sub epithelial area, early infiltration of lymphocytes is observed

Question 4

10 types of gingival fibers

Answer 4

dentogingival
alveologingival
transseptal
interpapillary
transgingival
dentoperiosteal
circular
periosteogingival
inter circular
inter gingival

Question 5

3 histological description of periodontitis

Answer 5

Increasing attachment and bone loss
Apical proliferation and partial ulceration of JE
In acute phase there might be bacterial invasion resulting in micro or macro abscess

Question 6

T/F gingivitis and periodontitis is caused by bacteria

Answer 6

F

Question 7

4 steps in pathogenesis of periodontitis

Answer 7

1. initial reaction to plaque
2. activation of macrophages
3. upregulation of inflammatory cells activity
4. Initial attachment loss

Question 8

3 events that occurs in Initial Reaction to Plaque

Answer 8

1. Bacterial products stimulates JE to synthesize inflammatory mediators (IL8, TNFa, IL1a, PGE2, MMP-breaks down collagen structure)
2. perivascular mast cells release histamine which cause endothelium to release IL8
3. IL8 attracts PMN which palisade and engulf bacteria, releasing cytokines (linking to adaptive)

Question 9

3 events that occurs in activation of macrophages

Answer 9

1. Vascular reaction cause complement to spill into CT and activates inflammatory pathway
2. leukocytes and monocytes are then recruited
3. Activated macrophages produces inflammatory mediators

Question 10

4 events that occurs in the upregulation of inflammatory cells activity

Answer 10

1. Activated T-cells coordinate response via cytokines
2. Plasma cells produces Igs and cytokines
3. Activated PMN synthesise cytokines, leukotrienes and MMP
4. Activated fibroblast produce MMP and TIMP instead of collagen and infiltrate expands

Question 11

2 key events that occur in the initial attachment lost phase

Answer 11

1. Immunocompetent cells produce cytokines MMP and TIMP leading to tissue destruction and bone resorption
2. Plasma cells becomes dominant in the ilfiltrate

Question 12

What can be used to block MMP

Answer 12

20 mg of doxycycline 2x a day

Question 13

What influences macrophage activity

Answer 13

Genetics, smoking(both causes hyper-responsive macrophage that increases pro-inflammatory cytokines) and NSAIDS(supressing PGE2)