Oral Bacteria Flashcards
where communities of bacteria are located in the mouth is determined by:
- binding sites
- oxygen level
- redox potential
- nutrients
- antagonism
- co-aggregation
nutrient source, pH, and redox potential in fissues
- saliva and diet
- neutral-acidic
- positive
nutrient source, pH, and redox potential in approximal surfaces
- saliva, diet, and gingival crevicular fluid (GCF)
- neutral-acidic
- slightly negative
in gingival crevice:
- GCF
- neutral-alkaline
- negative
where are anaerobic gram-negative rods found
the most in the gingival crevice, then in the approximal surfaces, and none/hardly any in the fissures
____ is found in every location in the mouth
S. mitis
____ and ____ are ubiquitously found on the tooth surface
s. sanguinis; s. gordonnii
____ group streptococci dominate the oral cavity and are pioneer colonizers
mitis
mitis group is major species in plaque (80%) and contains:
s. sanguinis
s. gordonnii
s. oralis
____ group is the minor species in healthy plaque and contains:
mutans; contains s. mutans and s. sobrinus
early (pioneer) colonizers include:
- streptococci (s. mitis, s. sanguinis, s. oralis, and s. gordonii)
- veillonella
- actinomyces
4 virulence factors of s. mutans
- acidogenic
- acid tolerant
- glycosyltransferases
- glucan binding proteins
acidogenic virulence factor
s. mutans has the ability to metabolize dietary carbohydrates and produce acid
acid tolerant VF
ATR (acid tolerance response)- more tolerant to acidic environment than commensal bacteria
glycosyltransferases (GTF)
extracellular enzymes that form polymers of glucose from sucrose, liberating fructose
glucan binding proteins (Gbp)
surface proteins that bind glucan
s.mutans metabolizes carbohydrates, producing:
lactic acid
acetic acid
formic acid
which then lowers the pH
GTFs produce ____ from _____
extracellular polysaccharide (EPS); sucrose
____ is associated with cariogenic plaque formation- binds everything together when ____ is present
water insoluble glucan; sucrose
bacteria that make up socransky’s red complex
- porphyromonas gingivalis (anaerobe)
- Tannerella forsythia (anaerobe)
- Treponema denticola (anaerobe)
characteristics of P. gingivalis
- gram negative rods
- obligate anaerobe
- asaccharolytic (ferments aa not sugar)
- requires iron to grow (hemin)
