Microflora of Dental Plaque Flashcards
Describe the features of teeth that make it beneficial for microbial colonisation (2)
- Hard
- Non-shedding
Why are pits and fissures of teeth good for microbial communities?
Offer protection from wider environment
What are gingival crevice bathed in?
Gingival crevicular fluid
How may bacteria on the tongue contribute to periodontal disease?
Back of the tongue can act as a reservoir for some gram negative anaerobes which may be present in periodontal diseases
What structures of the tongue may act as habitats for micro organisms?
Papillary surfaces of the dorsum of the tongue
What product found in saliva can influence aggregation and adhesion of bacteria to oral surfaces?
Glycoproteins in the saliva
How can some microbial communities be physically removed?
By saliva and GCF and then swallowed
How can saliva help remove microbial communities? (3)
- Physical removal
- Production of lysozyme which hydrolyse peptidoglycan in bacterial cell wall
- Production of lactoferrin which competes with bacteria for iron
What is the most prevalent bacteria in the adult oral cavity
Streptococci
What is the primary pathogen in aetiology of enamel caries in children and young adults?
Mutans Streptococcus
What is the relevance of the Streptococcus oralis group?
Opportunistic pathogens isolated frequently from infective endocarditis
Have to be aware when extracting tooth as bacteria could enter blood
What is the relevance of the Streptococcus milleri group?
Opportunistic pathogens important cause of purulent disease
What is the relevance of the Enterococcus?
Recovered in low numbers from several oral sites involved in root canal infections
What forms a major portion of plaque microflora (esp at approximate sites)?
Actinomyces
What is the relevance of the Eubacterium?
Anaerobic bacteria tat are involved with
Periodontitis;
Necrotic dental pulp;
Infections of the head, neck and lung
Name some microbes that are considered Gram-Positive Rods & Filaments (4)
- Actinomyces
- Eubacterium
- Lactobacillus
- Propionibacterium
What is the relevance of the Lactobacillus?
Involved in advanced caries lesion of enamel and root surface
Name two microbes that are are considered Gram Negative cocci
- Neisseria
- Veillonella
What is the relevance of the Neisseria?
Aerobic microbe that are among first colonisers of a clean tooth surface
What is the relevance of the Veillonella?
Anaerobic microbe that play an important role I dental plaque and caries
Where is Haemophilus spp commonly found?
Common in saliva, on
epithelial surfaces, and in dental plaque
Where is Capnocytophag spp commonly found?
Found in sub-gingival plaque
Where is actinomycetemcomitans (AA) commonly found?
Found in aggressive periodontitis
Where is Simonsiella commonly found?
Epethelial surfaces
Where is Porphyromonas gingivalis commonly found?
Found at subgingival sites
Where is Prevotella commonly found?
Isolated from dental plaque especially sub-gingival sites
Where is Fusobacterium commonly found?
Gingival crevice and periodontal pockets
What makes up the largest portion of the oral fungal flora?
C.albicans
