Periodontal Pathogens #5 Flashcards
T or F, Any accumulation of microorganisms at or below the gingival margin causes inflammation.
True!
T or F, All plaque bacteria is considered bad.
True
______ occurs when your mouth “recognizes a foe”
Ecological shift
Which is more important in disease concerning pathogen in the mouth, strains or species?
Strains
What are the prerequisites for disease initiation and progression with oral pathogens?
- Must express virulence factors
- Pathogen must be in the right location
- The local environment must not be to colonized by beneficial species (S.Sanguinis forms peroxide that inhibits pathogens)
- Host must be susceptible (immune compromised state)
What is Niche Saturation?
Primary colonizers saturate the realist and sub gingival sulcus (this is healthy) and prevent pathogen from colonizing there!
What are the 3 methods that help prevent pathogen colonization?
- Adhesins on bacteria bind to host receptors
- Coaggregation (nutrient utilization) = Veillonella uses lactate made by streptococci (these are found together and provide niche saturation)
- Competitive inhibition = bacteriocins are very nonspecific bactericide produced by bacteria. Also hydrogen peroxide production by S.Sanguinis inhibits A.a.
Why is A.a such a powerful bacteria?
Because it produces a very potent leukotoxin
How do pathogens overcome host defenses?
- Invade epithelium and bind to underlying cells (to prevent being sloughed off)
- IgG and IgA proteases and mimicking host antigens (to prevent antibodies from binding)
- Leukotoxin (A.a) and non-leathal suppression of immune (phagocytic cells)
Tell me about A.a….
- non motile
- gram negative
- Saccharolytic
- Capnophilic (needs co2)
- round ended rod
High numbers of A.a are associated with _______.
Agressive periodontitis
What are the Virulence factors of A.a?
- Tissue invasive (epithelial and endothelial)
- leukotoxins
- fibroblasts inhibiting factors
- Endotoxins
- Collagenase
High numbers of A.a are associated with _______.
Agressive periodontitis
What are the Virulence factors of A.a?
- Tissue invasive (epithelial and endothelial)
- leukotoxins
- fibroblasts inhibiting factors
- Endotoxins
- Collagenase
______ inhibits growth of A.a.
S. Sanguis (through peroxide production)