Gingivitis and Periodontitis

Question 1

What is the main difference between gingivitis and periodontitis?

Answer 1

Gingivitis = reversible inflammation to the gingiva

Periodontitis = irreversible infection associated with all parts of the periodontium

Question 2

What are the 4 stages of gingival inflammation?

Answer 2

1. Healthy / Prsitine gingiva
2. Initial lesion
3. Early lesion
4. Established lesion

Question 3

What are the key features of healthy gingiva?

Answer 3

No plaque
Shallow gingival sulcus
JE fimrly attached to root, sulcular epithelium, and connective tissue
Some gingival crevicular fluid (GCF)

Question 4

What are the clinical characteristics of healthy gingiva?

Answer 4

Pink or pigmented
Firm
No bleeding

Question 5

What are the histological characteristics of healthy gingiva?

Answer 5

JE coronal to cemento-enamel junction
Supragingival fibres intact
Alveolar bone intact
Periodontal ligament intact

Question 6

What are the clinical characteristics of gingivitis?

Answer 6

Erythemic (redness)
Inflamed
Bleeding present
Pain

Question 7

What are the histological characteristics of ginigivitis?

Answer 7

JE located at CEJ
Supragingival fibre destruction
PDL intact
Alveolar bone intact

Question 8

What changes occur during the inital lesion phase?

Answer 8

Within 2 - 4 days, bacteria colonise the tooth near the gingival margin, initiating host response

PMNs pass from bloodstream into the gingival conenctive tissue and release cytokines that destroy gingival connective tissue, allowing PMNs to move quickly through tissue

PMNs migrate into the sulcus and phagocytose bacteria, this process causes peri-vascular collagen loss

Question 9

What are prostaglandins (PG) and matrix metalloproteinase (MMP)?

Answer 9

PG = biochemical mediators, E series are crucial to perio bone destruction

MMP = family of enzymes that work together to break down connective tissue, causes extensinve destruction to collagen in pero tissues

Question 10

What changes occur during the early lesion (early gingivitis) phase?

Answer 10

Within 4 - 7 days, abcteria penetrate connective tissue and more PMNs are attracted to the site, releasing more cytokines and causing more localised destruction of connective tissue

Macrophages are recruited to the connective tissue and release cytokines, PGE2, and MMPs (more destruction)

JE and sulcus become densely infiltrated by neutrophils and begin to show development of rete pegs/ridges

Increased collagen destruction (70% around infiltrate destroyed), affecting circular and dentoginigval fibre groups, collagen production decreases

Question 11

What changes occur diring the established lesion phase?

Answer 11

Within 14 - 21 days, plaque biofilm extends subgingivally and disrupts the attachment of the most coronal portion of the JE

Macrophages and lymphocytes are most numerous in the connective tissue, PMNs continue to fight bacteria in the sulcus, so host cells continue to produce more toxic chemicals (cytokines, PGE2, and MMPs)

Blood vessels engorged and congested as venous return is impaired, blood flow is sluggish and localised gingival anoxemia gives bluish hue

Moderate / severely inflammed gingiva and deepening of gingival sulcus, but NO LOA

Question 12

What is periodontitis?

Answer 12

Bacterial infection of the periodontium associated with the body’s response to bacterial invasion of the JE and connective tissue

Process is usually pain free, patient present to the clinci after noticing bleeding gums or mobile teeth

Eventually bony socket of the tooth is compromised adn the tooth becomes mobile

Question 13

What are the clinical characteristics of periodontitis?

Answer 13

• Colour varies from red and purplish-blue
• Bleeding on probing
• Inflammed or fibrotic gingiva
• Increased pocket depths > 3mm
• Recession
• Bone resoprtion
• Drifiting of teeth
• Tooth mobility
• Suppuration on probing (pus formation)

Question 14

What are the histological characteristics of periodontitis?

Answer 14

• Coronal portion of JE detaches from root surface
• Apical portion fo JE moves apically along surface of root creating a periodontal pocket
• Collagen fibres are destroyed
• Permanent destruction of alveolar bone and periodontal fibres
• Cementum is exposed to oral environment

Question 15

What is the mechanism of alveolar bone destruction?

Answer 15

Macrophages produce cytokines, PGE2, and MMPs which stimulate fibroblasts and secrete more PGE2 and MMPs

Mediators from macrophages and fibroblasts result in destruction of the connective tissue and PGE2 stimualte osetoclasts and resorb the crest of the alveolar bone

Question 16

What are the characteristics of suprabony pockets / horizontal bone loss?

Answer 16

Inflammation spreads within the conenctive tissue into alveolar bone then into the periodontal space

This pathway is least resistant due to periodontal fibres

Base of JE forming the pocket is located above the coronal portion of the alveolar crest (supracrestal) and results in an even pattern of bone loss

Question 17

What are the characteristics of infrabony pockets / vertical bone loss?

Answer 17

Pathway directly to periodontal ligament (PDL) space

Inflammation spreads from gingiva to the PDL space then finally into alveolar bone, resultign in uneven patterns of bone loss

Bas eof JE forming the pocket is loaced BELOW the crest of the alveolar bone (subcrestal)

Question 18

What is the difference between an active adn inactive periodontal pocket?

Answer 18

Active site = continued apical migration of the JE over time, bleeding on probing

Inactive site = stabilised periodontal pocket over time

regular periodontal analysis is necessary to monitor progression of disease