Periodontal Microbiology Flashcards
what factors influence the oral microflora
host factors
diet
saliva
gingival crevicular fluid
microbial interactions
gaseous environment
what are the classifications of periodontal disease
gingivitis
periodontitis - chronic or aggressive
necrotising periodontitis
peri-implantitis
what host factors can influence the start of periodontal disease
smoking
genetics
pregnancy
systemic disease
nutrition
how does periodontitis develop
high concentrations of periodontitis causing bacteria causes severe inflammation and pocket formation leading to degradation of soft and bone tissue
what bacteria can cause periodontal diseases
P. gingivalis
prevotella intermedia
AA
describe P gingivalis
gram negative, non-motile rod, strict anaerobe
what are some virulence factors of P gingivalis
host cell tissue adherence and invasion
elaboration of proteases - leads to lots of degradative enzymes
endotoxins
capsular polysaccharide and outer membrane vesicles
tissue toxic metabolic by-products
what enables P gingivalis to adhenre and invade the host cell tissue
fimbriae
what are the cocktail of degradative enzymes associated with P gingivalis
collagenase
fibrinolysin
phospholipase A
phosphotases
what are the tissue toxic by-products of P gingivalis
hydrogen sulphide
ammonia
fatty acids
how do fimbrillar adhesins help invade host cells
bind to their cellular integrins
what are the two types of fimbriae
long (FimA) - inital attachment and biofilm organisation
short (Mfa1) - microcolony formation by cell to cell autoaggregation
what is a biofilm
community of microbes attached to a surface
what are the development phases of biofilm formation
host salivary glycoproteins, linking fim
coaggregation, re-conditiong film, accumulation and shedding
what occurs to biofilm as disease moves from health the perio
the number and severity of pathogens increases
what are the stages in biofilm development
adhesion
colonisation
accumulation
complex community
dispersal
what microorganisms may be associated with oral health
oral streptococci
fusobacterium
what is Socransky’s model
relationship of species within microbial complexes
how do microbes act competitively
metabolic products - acids, oxidants
bacteriocins
receptor antagonism
how do microbe act co-operatively
metabolic products - saccharides, peptides, growth factors
adhesion substrates
immune avoidance
what is the healthy plaque theory
if you modify the environment the healthy plaque can change to diseased
give examples of changing a microbiome
broad scale antibiotics
chlorhexidine mouthwash
what microorganism is very important for the aggregation of other pathogenic molecules
fusobacterium nucleatum
what is Koch’s postulates
you would be able to isolate the disease and then entering it into an animal host and it would cause the disease you are investigating
