Periodontal Disease Flashcards
Inflammation? Definition?
The reaction of living tissue to injury or infection
Immunity? Definition?
The ability of an organism to
resist disease, through the activities of specialised blood cells or antibodies produced
by them in response to natural exposure or inoculation
Adaptive vs Innate? Differences?
Innate: No time lag, not antigen specific and no memory
Adaptive: Lag period, antigen specific and memory development
Innate immunity? Dental-related?
Saliva, Epithelium and Inflammatory response
Saliva: prevents drying, antimicrobial (IgA, peroxidase, lysozyme and lactoferrin)
Epithelium: physical, inflammatroy via keratinocytes and immune response via macrophages
Inflammatory response: GCF, neutrophils and macrophages
Saliva? Immunity characteristics?
- Stimulate gut secretory immune system
- Activated gut lympho migrate to sailavry gland and secrete IgA, influencing bacterial attachment and allowing them to be swallowed
- Peroxidase kills bacteria
lysozyme weakens +ve wall - Lactoferrin binds iron for bacterial growth
Oral Mucosal Surfaces? Immunity characteristics?
IgA Mucins Saliva Serum IgG Langerhans' cells Membrane coating
Epithelium? Immunity characteristics?
Physical
Inflamm response via Keratinocytes
Immune via Langerhans’
Junctional epithelium? Immunity characteristics?
High cell turnover
Neutophils found in JE migrate to sulcus (role in jost defence)
Cells maintained in early maturation, which in-turn does not form membrane coating granules, and so JE is permeable to some plaque
Inflammatory response? JE?
Cells in JE release IL-1/8, TNF-a and cytokine-induced neutrophil chemo-attractant-2
Immune response? JE
Langerhan’s cells
Features of inflammation?
Pain Swelling Redness Increased temperature Loss of function
Cells of the immune system? Differentiation?
Stem cells form Lymphoid stem cells and myeloid progenitor cells
LSC - B cell, T cell and NK
B - Plasma and memory
T - helper and killer
MP - neutro, eosino, baso, mast and mono
Mono form dendritic and macrophages
Neutrophils? Function? Bacteria in plaque matrix vs unattached?
In plaque matrix:
- neutrophil attach to plaque
- secretes enzymes and H2O2
- kills bacteria
- plaque dissolved
- washed away by GCF
- damaged caused
Unattached:
- neutrophils recog and bind bacteria, phago into vacuole
- produces antibac granules and H2O2
- digest bacteria
- remnants expelled
- damage caused
Macrophage? Function? Inflammation vs Immunity?
Inflammation:
- phago dead and dying cells
- modulate fluid and cellular components
- secrete tissue-degrad zymes
- secrete IL-1, TNF-a and prostagl
Immunity:
- traps and presents antigen, while CD44 acts as anchor
- secrete IL-1/TNF-a
Humoral response? Process?
- Langerhans’ cells take antigen to lymph nodes and present to lymphocytes – clonal expansion
- B-lymphocytes differentiate into plasma cells and secrete antibody against antigen
- Antibody thought to be protective – IgG, IgA
- Antibody produced systemically or locally.
Aggregate micro-organisms, activate complement system to lyse bacteria, opsonisation + phagocytosis via neutrophils - Antibody titres vary between individuals, and in response to treatment
- High levels indicate either positive immune response or an inability to eliminate pathogen
- Antibody avidity is a measure of effective immune function.
Local antibody production? JE? Process?
- Plaque antigen diffuses through JE
- Langerhans capture antigen in JE
- APC leave gingiva in lymphatics
- APC reach lymph node and stimulate specific immune response
- specific abs are produced by plasma cells within lymph node and travel back to gingiva via BVs
- Abs leave circulation and are carried to the crevice in the transudate
- Abs bind to antigen causing aggregation, precipitation, detox, opson and phago.
Cell mediated response? JE?
No Antibody involvement
1. Antigen processed and presented to T Cell
Receptor on T-helper cell (Th1, Th2)
2. T-helper lymphocytes produce cytokines to assist
B-cell differentiation into Plasma Cells, or activate
Neutrophils and Macrophages
3. T-helper 1 cells stimulate cytotoxic T Cells (Tc) –
Aggregatibacter Actinomycetemcomitans
Gingivitis – predominantly T cell response
Periodontitis – predominantly B Cell / Plasma Cell
response
Bone destruction? -ve vs +ve?
-ve:
- LPS
+ve:
- peptidoglycan
Walls have different effects on the communication of the cells
Act complement
5 stages of periodontitis development?
Pristine gingiva Initial lesion Early lesion Established lesion Advanced Lesion
Pristine gingiva? Characteristics?
Free from histological inflammation, however this cannot be achieved due to the presence of bacteria
Classification of 2017 created clinical gingival health
Initial lesion? Characteristics?
- Inflammation within 24 hours of plaque accumulation – Vasodilation, ↑ GCF
- Neutrophils migrate into gingival sulcus (ICAM-1, ELAM-1)
- A few lymphocytes / macrophages
- Lymphocytes bind to connective tissue (CD44)
- Cellular Response develops in 2-4 days
- Plaque form on supragingiva
- WBCs in JE
- Increased vasc in CT
Under the new guidelines this is considered ‘Clinical Gingival Health’
Early lesion (1 week)? Characteristics?
- Inflammatory infiltrate increases
- Vessels dilated / More vessels
- ↑ Lymphocytes + - —-Neutrophils
• Very Few Plasma Cells
• Fibroblasts show cell damage - Loss of Gingival Collagen
Basal cells of Junctional +
Sulcular epithelium proliferate (Mechanical Barrier)
• Rete Peg Proliferation
• Some Coronal Epithelium lost
– plaque starts to extend
subgingivally
• Can Persist without
progressing to Established
Gingivitis - Plaque biofilm formation
- Intact alveolar bone
- CEJ still at JE
Established lesion? Characteristics?
- ↑ GCF
- ↑ Inflammatory infiltrate
- Neutrophils predominate, ↑ Migration
- Plasma Cells form 10-30% of infiltrate
- Fibroblasts continue to show cell damage
- Loss of Gingival Collagen
Laterally and Apically - Rete Pegs extend further
- Junctional epithelium no
longer closely attached to
tooth – “False Pocket” - Gingivae Red + Swollen
- May remain stable or progress to Periodontitis (final stage)
- Supragingival plaque extending subgingivally
Gingivitis classification?
Clinical Gingival Health: no attachment loss and less than 10% BOP
Localised Gingivitis: no attachement loss and between 10-30% BOP
Generalised Gingivitis: no attached loss and greater than 30% BOP
Advanced Lesion (Suprabony)(Periodontitis)? Characteristics?
- Inflammatory infiltrate extends apically and laterally
- Plasma cells predominate (>50% of cell types)
- Loss of periodontal connective tissue attachment
- Apical Migration of Junctional Epithelium – True pocket formation
- Alveolar Bone Loss
- Periodontitis (Stage 1)
in this example as up
to 10% bone loss - Loss of attachment 1-2mm
- Pocket 4-5mm
- Pocket epithelium (ulcerated and leaky)
- Subgingival calculus covered by plaque
Advanced Lesion (Infrabony)(Periodontitis)? Characteristics?
- Same as Suprabony but 10-33% bone loss (stage 2)
- Loss of attachment 3-4mm
Gingivitis to Periodontitis progression?
- Regulated by variable expression of integrands and
other adhesion molecules at the epithelial –
connective tissue interface (ICAM-1, ELAM-1, CD44).
Matrix Metalloproteinases
Reactive Oxygen Species
Cytokines & Growth Factors • Platelet Derived Growth Factor (PDGF) • Insulin-like Growth Factor (IGF) • Interleukin-1 (IL-1) • Transforming Growth Factor β (TGF- β) • Prostaglandin E2 (PGE2) • Interferon γ (IFN- γ)
Matrix Metalloproteinases? Aid periodontitis progression process?
- MMPs synth and secreted by inactive precursor, converted to active (activation by proteinases)
- GF and cytokine reg MMP production (IL-1 and TGF-b)
- serum and tissue inhibitors neutralise activity of MMP
- TIMP prevet conversion of precursor of MMPs to active form
Asynchronous multiple burst theory? Clinical attachment loss (CAL)
- Multiple active sites break down within a short time, with long periods of quiescence
- Periods of activity may be clustered around phases of patient’s life (risk factors)
Periodontal tissue healing? Process? Overview?
- Starts with acute inflammation (24-48hrs)
- Dental treatment and maintenance leads to healing
- Includes reduced:
vasodilation, gingival crevicular fluid, inflamm cells and the pocket ulceration heals - Fibroblasts prolif forming collagen fibres and ground substance forming mature CT
- Formation of long JE and bony remodelling
Bacterial flora? Characteristics during healing?
- Reduction in total numbers
- Shift from -ve anaerobes to -ve aerobes
- From disease associated to health
- Reduction in plaque bulk
1 week post-treatment from advanced lesion? Composition?
- Reduction in number of neutrophils in gingival crevice
- CT infiltrate reduces
- Reduction in gingival swelling
- Pocket ulceration healing
- Fibroblast prolif