Dental disease- Periodontal disease

Question 1

What do we expect to see in healthy gingvia?

Answer 1

Colour: pink

Texture: stipling

Margins: defined (knife edge and scalloped)

Question 2

What is gingival crevicular fluid?

Answer 2

This is liquid that contains antibodies and so is used for host defence.

Question 3

What do you see in the mouth of a patient with gingivitis?

Answer 3

Colour: red

Texture: no stipling

Margins: inflamed.

Plaque score: high

Bleeding score: high

Question 4

Compare the immune response occuring in a healthy mouth compared to one that is suffering from gingivitis?

Answer 4

Healthy mouth:

• some gingival crevicular fluid
• Phagocytes/ Lymphocytes and complement.

Gingivitis:

• Increased flow of gingival crevicular fluid
• Increased lymphocytes and monocytes.
• Influx of neutrophils.

Question 5

Why do the gingiva bleed on probing?

Answer 5

Because the Epithelium becomes uclerated

Question 6

Why does cleaning teeth reverse gingivitis?

Answer 6

It removes the microbial challenge.

Question 7

Compare gingivitis and periodontitis (definitions)

Answer 7

Gingivitis is inflamation of the soft tissues.

Periodontitis is inflamation of the soft and hard tissues.

Question 8

At first sight- How does a patient presenting with periodontitis differ to a patient with gingivitis?

Answer 8

At first glance, they don’t.

You need to probe in order to see the difference.

On probing a patient with periodontitis will have pockets.

Question 9

Compare true and false pockets

Answer 9

True pockets are when the pockets are due to LOSS of attachment and migration of the junctional epithelium.

False pockets are due to inflamation of the tissues.

Question 10

Discuss the loss of attachment in a dental patient?

Answer 10

The rate of loss of attachment can be unpredictable so we have to monitor it.

Question 11

What is the biofilm?

Answer 11

A layer of micro-organsisms found on the teeth- They interact in symbiosis.

Question 12

Describe the biofilm in a patient suffering from periodontitis?

Answer 12

It is dysbiotic = unbalanced. Causing the inflammation

Question 13

Discuss the mechansims that contribute to the mouth’s host immune response

Answer 13

Saliva- the immune response that protects the teeth (made of antiboides and enzymes e.g. S-Iga/ lyzozyme)

Gingival Crevicular fluid (will bathe the area)

Inflammatory and Immune response (neutrophils)

Epithelium (as a physical barrier which sheds cells and produces inflammatory mediators. The gingival tissues allow neutrophils to transvere through)

Question 14

What determines bone resorption?

Answer 14

The inflamatory Mediators produced.

Question 15

How do antibodies protect the immune system?

Answer 15

activating complement

marking bacteria (opzonisation) for phagocytosis

inhibiting adhesion and invasion

Neutralising toxins.

Question 16

What are MMPs?

Answer 16

Matrix metalloproteinases which are enzymes that cause matrix degradation in periodontitis.

Question 17

What is the normal level of bone?

Answer 17

1-2mm below the ADJ

Question 18

Name and compare the different patterns of bone loss

Answer 18

Vertical bone loss- This occurs in thicker bone as the diameter will not reach the full bone.

Bone depth differs on either side

Horizontal bone loss- This occurs in thinner bone as the 2mm diameter of tissue destruction damages all of the bone.

Bone depth is the same.

Furcation bone loss- when bone is lost and the furcation regions are exposed.

Question 19

Which type of bone loss has a greater chance at re-generation and why?

Answer 19

Vertical bone loss as there is a wall of bone where you can pack re-generative materials.

Question 20

Why is smoking a risk factor of periodontal disease?

Answer 20

Smoking affects your immune system. This affects your immune response. So when the bacteria change, the patient is more likely to get Periodontal disease.

Smoking also makes the treatment less succesful

Question 21

What are the local risk factors of periodontal disease?

Answer 21

• Anatomical :Enamel pearls, grooves, furcations, gingival recession.
• Tooth position- malalignment/ tooth crowding/ tiping/ migration and occlusal forces.

Iatrogenic- overhangs/ orthodontic appliances/defective margins and poorly designed RPDs.

Question 22

What do you see in the mouth of a patient with periodontitis?

Answer 22

Bleeding = on probing

Radiographic bone loss (mobility of teeth)

Gingival recession

Probing depth of >4mm

Splaying of teeth.

Question 23

What instrument do we use to measure peridontal pockets?

Answer 23

WHO CPITN BPE probe

Question 24

What triggers Periodontal disease?

Answer 24

• Plaque and calculus accumulation
• Biofilm components
• Expression of Virulence factors

Question 25

What determines if inflammation will progress or resolve?

Answer 25

The interaction between the host immune response and the bacteria.

Question 26

Discuss P. Gingivalis.

Answer 26

ascaccharolytic- energy source is provided by proteins and peptides. It is inflammaphillic- Inflammatory environment favours the production of these virulence factors: **Gingipans**- proteases that degrade host proteins and activate mmps **Atypical LPS**- do not signal through TLR 4

Question 27

Describe the pathogenesis of a patient suffering from gingivitis.

Answer 27

1. increased TLR stimulation 2. Increased production of pro-inflammation mediators 3. Acute inflammatory response Clinical- red and swollen function- To increase vasodilation and cell migration 4. Increased gingival crevicular fluid 5. number of neutrophils in area increases 6. monocytes are recruited, activated and differentiate into macrophages. 7. Lymphocytes are recruited to fine tune the immune response.

Question 28

What causes tissue destruction by neutrophils?

Answer 28

* Degradative enzymes (major source of MMPS) * Oxygen radicals and inflammatory cytokines.

Question 29

How does an immune over-reaction cause periodontitis?

Answer 29

There is an excess of neutrophils- This causes tissue destruction

Question 30

How does an immune under-reaction cause periodontitis.

Answer 30

There are not enough neutrophils. This allows oral bacteria to run riot and cause tissue damage.

Question 31

What are the roles of adaptive immunity?

Answer 31

Protective : Prevention of systemic infection. Destructive- Inflammation causing alveolar bone loss.

Question 32

Describe the stages leading to inflammation.

Answer 32

T & B cells present in early lesions (gingivitis) Lesion progresses- Rich in CD4 T cells(helper)/ B cells (antibody response) and dendritic cells (antigen presenting) Dysbiotic biofilm cannot be controlled. Periodontitis- B cells and Plasma cells. IgG cannot control dsybiotic Chronic inflammation.

Question 33

Describe bone formation and resorption in health.

Answer 33

RANKL is produced by leukocytes. RANK binds to RANKL to activate osteoclasts (bone resorption) OPG inhibits RANK binding to RANKL Allowing bone synthesis

Question 34

Describe bone resorption in inflammation.

Answer 34

There is high levels of RANKL and low levels of OPG. So bone resorption exceeds bone synthesis.

Question 35

Discuss the inflammatory response in periodontitis?

Answer 35

1. TLR stimulated. causing secretion of Cytokines chemokines and AMP. 2. Vasodilation and selective leukocyte recruitment (mainly neutrophils) 3. Bacterial products activate neutrophils & stimulate the secretion of inflammatory mediators. 4. Activated lymphocytes express RANKL 5. Alveolar bone resorption because - RANK binds to RANKL - Pro-inflammatory cytokines inhibit bone formation. - Elevated and dysregulated mmp activation.