Transcript Dental Plaque Biofilms - Ministry of Public Health

Dental Plaque Biofilms
Teradaj Aticharoenkul
Periodontal disease
chronic imflammatory lesions
 destruction
 supporting periodontal tissues
 associated with specific microbial complexes
in subgingival biofilms

Bacterial species
Actinobacillus actinomycetemcomitans
 Actinomyces odonlyticus
 Actinomyces naeslundii
 Capnocytophaga gingivalis
 Fusobacterium nucleatum
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Bacterial species
Streptococcus mitis
 Eubacterium nodatum
 Propionibacterium acres
 Porphyromonas gingivalis
 Treponema denticola
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Treponema denticola
Gram negative oral spirochete
 predominant of human periodontal disease
 infection and inflammation of gingiva
 occurs in 80% of the adult population
 lives and can evolve to severe

Treponema denticola
refractory periodontitis
 acute necrotizing gingivitis
 bone resorption and tooth loss

Biofilm communities

Comprises : bacterial microcolonies,
extracellular slime layer, fluid channels and
primitive communication system
Biofilm communities
• bacteria attach to a surface
• mushroom-shaped
microcolonies
• different microcolonies may
contain different combinations
of bacterial species
• the slime layer protects the
bacterial microcolonies from
antibiotics,antimicrobials,and
host defense mechanisms
Biofilm communities
• bacteria in the center of a
microcolony may live in a
strict anaerobic environment
• while other bacteria at the
edges of the fluid channels
may live in an aerobic
environment
Biofilm communities
• the biofilm structure provides
a range of customized living
environments (with differing
pHs, nutrient availability, and
oxygen)
• within which bacteria with
different physiological needs
can survive
• fluid channels penetrates the
extracellular slime layer
Biofilm communities
• fluid channels provide
nutrients and oxygen for the
bacterial micro colonies and
facilitate movement of
bacterial metabolites, waste
products, and enzymes within
the biofilm structure
• Each bacterial microcolony
uses chemical signals to
create a primitive
communication system used
to communicate with other
bacterial microcolonies
Phases of plaque formation
Phases of plaque formation
The pattern of biofilm development
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Cell division of the attached cells
to produce confluent growth,
and a bioflim.
secondary or late-colonisers
attach to primary colonisers
(coaggregation)
irreversible adhesion
adhesins on the cell surface and
receptors in the acquired
pellicle.
shorter-range (10-20nm)
interactions
result in reversible adhesion to
the surface.
long-range (>5Onm), nonspecific interaction of microbial
cell surfaces with the acquired
pellicle
absorption of salivary proteins
and glycoproteins
some bacterial molecules, to the
tooth surface (the acquired
pellicle)