___ ___ contribute significantly to the development of dental caries
Mutans streptococci
6 species in Mutans Streptococci
S. mutans
S. sobrinus
S. ratti
S. criceti
S. downei
S. macacae
Saliva can be good for bacteria because it provides the pellicle, which does what?
it facilitates bacterial adhesion
Saliva provides what for bacteria?
Nutrients
Saliva can inhibit the growth of bacteria thorough non-specific factors such as (2)
lysozyme--> involved in the lysis of bacteria
lactoferrin--> sequesters iron
Saliva can inhibit the growth of bacteria thorough specific factors such as (2)
IgA
Other Immunoglobulins
What antimicrobial does saliva produce through the sialoperoxidase system?
Hypothiocyanite (OSCN-)
Saliva can aggregate bacteria--> how is this good and bad for the bacteria?
Bad: can result in the clearance of bacteria from mouth
Good: can results in the deposition of bacteria on certain surfaces
What 4 inter and intraspecies processes do oral microbes engage in that can promote and suppress the growth of other microbes
Competition for receptors for adhesion
Production of bacteriocins that can kill other microbes
Production of metabolic end-products, which can intoxicate other bacteria
utilization of metabolic end-products of other bacteria as nutrients
T/F: dental plaque biofilms are a community composed of the same microbe
False--> different microbes
T/F: biofilms contain only living microbes
FALSE--> it contains living as well as dead and dying microbes
T/F: plaque can be found on hard AND soft tissue surfaces of the mouth
TRUE!
___ biofilms microbes display greater resistance to antimicrobials than ____
sessile (encased in a biofilm)
planktonic (free-living forms)
What three bacteria (other than S. mutants) play a role in dental caries (cariogenic)
Lactobacilli
Actinomyces
Veillonella
Cariogenic flora are characterized by what three things
acidogenicity--> metabolizes sugar to acids
aciduricty--> tolerates conditions of low pH
ability to synthesize extracellular and intracellular polysaccharides
saliva can modulate the growth of bacteria through its maintenance of ____
pH
what bacteria extracellular enzymes convert sucrose to glucose and fructose?
glucosyl and fructosyl transferase
glucose and fructose are concerted to ___ and ____ with are utilized as a major food source but the bacteria and also as components of plaque matrix
Glucans and fructans
high caries risk might correlate with greater than ______ S. mutans colony forming units per mL of saliva and greater than ____ lactobacillus CFU per mL of saliva
one million
100,000
gingival health is characterized by mainly what bacteria?
Gram-positive aerobic cocci (with fewer than 5% of organisms being spirochetes and motile rods)
With increasing severity of gingival disease, there is an increase in proportions of what bacteria?
Strict anaerobic, gram-negative and motile bacteria
5 bacteria associated with a healthy gingival sulcus
Strep sanguis
Strep oralis
Actinomyces naeslundi
Actinomyces viscosus
Veillonella
4 bacteria associated with aggressive periodontitis
Actinobacillus actinomycetemcomitans
Capnocytophaga
Porphyporymonas gingivalis
Prevotella intermedia
What 2 microbes are associated with necrotizing ulcerative gingivitis (NUG)--anaerobic polymicrobial infection
Fusobacterium nucleatum
Spirochetes
5 ways to test for presence of possible peridontopathogens
