Oral environment /dental plaque Flashcards
Name things found within the oral environment
Teeth/gingivia/palate
Tongue and parts - papillae /lyphoid tissues ( tonsils)
Saliva and Gingivae crevicular fluid
Microorganism
Food and nutritional requirements
What is a biofilm
complex structure of micro-communities
Name 2 known dental carie microbes
Streptococcus mutant- Gram positive
Lactobacilli
What causes denture stomatitis
Candidia albicans ( yeast (fungus))
Name 2 microbes that are dental friends
St. Salivarius
S. sanguines
S. mitins
Name 3 requirements for microbe colonisation
Nutritional requirements
Adherence to withstand local clearance mechanisms eg saliva flow rate ,lysozymes ,gingival crevicular fluid and IgG immunoglobulins
Tolerance to environment conditions- e.g pH , lysozymes
What is an aerobic microbe mean
needs atmospheric Oxygen levels ( unusual in mouth
What does micro-aerophilic mean
Prefer low oxygen levels
What does capnophilic mean
prefer low oxygen high CO2 levels
What’s a facultative anaerobic microbe
One that grows in both aerobic and anerobic conditions
What’s an obligate anaerobe
Poisoned by oxygen
What’s an aerotolerant microbe
has anaerobic metabolism however not sensitive to oxygen
What 4 environment areas can microbes attach
Tooth surface
Gingival crevice
Hard palate
Mucosal surfaces
What is the significance of dental plaque
causes dental caries
gingivitis
periodontal disease
What is the definition of a dental plague
a biofilm , complex microbial community found on a tooth surface embedded in a matrix of polymers of bacteria and salivary origin
Can you remove plaque with a jet of water
NO
What is materia alba
A white deposit that can be removed by a jet of water
What is the composition of plaque
80-90% metabolising bacteria
10-20 % inter microbial matrix ( bacteria and salivary polymers)
How do plaques develop
Tooth surface COLONISED by bacteria adhering to the acquired pellicle surface by receptors
Pellicle selectively absorbs salivary macromolecules
Initially attachment weak but bacteria make extracellular polysaccharides so becomes sticky and more adherence to surface occurs -more bacteria join
Nutrition via foods and changes to pH favouring these bacteria increase the survival and they start to make lactic acid which starts tooth decay demineralisation process
Name 4 locations plaque deposits
Smooth surface plaque on tooth surface
Fissure plaque
Gingival plaque
Approximate plaque
Describe 5 details of supra gingival plaque
Bathed in saliva
Carbohydrate fermenters( acidogenic)
Microaerophilic’
Gram +ve cocci or filamentous
Cause dental caries
Describe 5 details of subginigivial palque
Bathed in gingival crevicular fluid
Breakdown protein ( proteolytic and saccharolytic- stinky )
Anaerobic’
Gram -ve rods /fusiforms
Cause periodontal disease
What’s a dental calculus
Non viable mineralised adherent calcified deposit on teeth and other solid structures
Associated with periodontal disease
Name 4 nutritional sources to mouth bacteria
Hosts diet - carbohydrates/proteins/lipids
Hosts damaged cells
Bacteria - other bacteria - dead or alive
Oral secretions -saliva ( supra gingival )
-gingival crevicular fluid ( subgingival )
What is gingival crevicular fluid
an inflammatory exudate from periodontal tissues.
Its composed of serum and locally generated materials (tissue breakdown products, inflammatory mediators, and antibodies directed against dental plaque bacteria. )
why is gingival crevicular fluid important
It helps maintain the structure of junctional epithelium and the antimicrobial defense of periodontium.
what causes acute necrotic gingivitis
Gram -ve anaerobes + stress/smoking factors
what is Socranskys red complex
Group bacteria causes severe periodontal disease ( P.ginivalis main one )
