Periodontitis Flashcards
What are examples of oral biofilm diseases?
- caries
- endodontic infections
- periodontal infection
- oral malodur (dorsal surface of tongue)
- mucosal iinfections
What 6 groups of things can influence the oral microflora?
- host factors
- diet
- saliva
- gingival and crevicular fluid
- microbial interactions
- gaseous environment (O2 concentrations)
What host factors can influence the oral microflora?
- systemic disease
- antibiotic use
- oral hygiene methods
What diet factors can influence the oral microflora?
- chemical composition
- physical consistency
- frequency of intake
How can saliva influnce the oral microflora?
- flow rate
- pH balance
- antimicrobial factors
how do microbial interactions influence the oral microflora?
-competition and co-operation
dysbiotic biofilms have a detrimental affect on health
How does gingival crevicular fluid influence oral microflora?
has antimicrobial components and humoral immunity -helps protect
What host factors can influence periodontal disease?
- smoking
- genetics
- pregnancy/puberty
- systemic disease
- nutrition
Describe the progression from health to gingivitis to periodontitis. (microbiology)
health = colonisation with normal oral flora and healthy gingiva
Gingivitis = proportion of periosontapathogenic bacteria increases. Mild inflammation at the edge of the gum
What are the stages in biofilm development?
- adhesion
- colonization
- accumulation
- complex community
- dispersal/shedding
What are some important organisms found in health?
- oral streptococci
- actinomyces
- fusobacterium
What are some important organisms found in gingivitis?
-actinomyces
=precotella intermedia
-bacteroides
What are some important organisms founf in periodontitis?
P. gingivalis
T. denticola
T. forsythia
P. intermedia
Describe P. gingivalis
gram -ve non-motile rod
Strict anerobe
What are some virulence factors of P. gingivalis?
- host cell tissue adherence and invasion (fimbriae)
- elaboration of proteases (cocktail of degradative enzymes)
- endotoxin (LPS)
- cpsula polysaccharide and outer membrane vesicles
- tissue toxic metabolic by-products
P.gingivalis adheres via fimbriae. How do fimbria help attachment and what are the types you get?
Help invade membrane vesicle of host cells by binding to cellular integrins
Get short and long fimbrae
How does P.gingivalis manipulate host defences?
- biofilm lifestyle
- induction of tissue destrucion (MMP’s)
- subversion - intracellular and tricking host immunity
What are some virulence factors of A.a. (A actinomyecetemcomitans)
- leukotoxin
- cytotoxin
- LPS
- Fc binding proteins
- fimbriaw
- glycoprotein matrix
- phase variation
- subvert host cell immunity
