1. Periodontitis Flashcards
Pathogenesis of gingivitis (2)
Microbial challenge (plaque) leads to clinical disease (gingivitis)
Types of local plaque retention factors (4)
Calculus
Restoration margins
Crowding
Mouth breathing
Types of systemic modifying factors (2)
Sex hormones
Medication
Features of gingival health (6)
Knife-edge, scalloped gingival margin Stippling (in about 30% of cases) Pink/pale colour Firm and flat gum tissues Painless No bleeding
Specific features of health (6)
Intact barrier provided by junctional epithelium
Shedding of oral epithelial cells
Flow of GCF
Antibodies in GCF
Phagocyte function and lymphocyte infiltrate
Complement activity
Definition of gingivitis (2)
Inflammation of the gingiva
Commonly occurs because of films of bacteria that accumulate on the teeth (plaque)
Signs of gingivitis (8)
Red or bluish red (chronic inflammation) colour Bleeding on provocation/probing Loss of stippling Pus Inflammation (oedema - swollen gums) Bad breath Receding gingiva Occasionally painful
Features of gingivitis (7)
Altered microbial colonisation
Increased flow of GCF
Influx of neutrophils, increased lymphocytes and monocytes
Increased flow of GCF
Influx of neutrophils, increased lymphocytes and monocytes
Plasma cell infiltrate
Proliferation and ulceration of epithelium
Biofilm features in health (2)
Biofilm is gram-negative
Biofilm is aerobic
Biofilm features in disease (2)
Biofilm is gram-positive
Biofilm is anaerobic
Removal of microbial challenge leads to
A return to health
Definition of periodontitis
Inflammation of the gums and supporting structures of the teeth
Causes of periodontitis (2)
Certain bacteria
Local inflammation triggered by those bacteria
Definition of biofilm
One or more communities of micro-organisms, embedded in a glycoalyx, attached to a solid surface
How is a biofilm removed
Mechanical disruption
Function of biofilm (3)
Provide protection for colonising species from competing organisms and environment (host defences, antibiotics)
Facilitate uptake of nutrients and removal of metabolic products
Allow for development of appropriate physiochemical environment (pH, O2 conc.) and allow for communication between bacteria
Features of late colonisers (2)
Associated with periodontal disease
Require a fairly established biofilm before being able to colonise
Definition of bacterial virulence (2)
Ability to colonise and compete in an ecological niche
The ability to evade host defences by degrade host Ig and complement leukotoxin production, tissue invasion and inhibition of antibody synthesis
Evidence for specific bacterial causation (4)
Presence in elevated numbers at diseased sites
Reduced number following periodontal therapy
Presence of an elevated specific immune response
Evidence from animal models
What is required for periodontitis to occur
Presence of bacteria
Host immune response mechanisms in the mouth (4)
Saliva
Epithelium (physical barrier, shedding of cells, production of inflammatory mediators)
GCF
Inflammatory and immune responses (inflammatory cells, PMNs, etc.)
Protective functions of the antibody (4)
Inhibition of adhesion/invasion
Complement activation
Neutralisation of toxins
Opsonisation and phagocytosis
How does CT matrix degradation occur
Through MMPs
What are MMPs (2)
Matrix metalloproteinases are a family of Zn and Ca-dependent proteolytic enzymes (including collagenases)
In periodontitis, matrix degradation is largely a result of MMPs secreted by host inflammatory cells
