Oral Biofilm Flashcards
(18 cards)
What is plaque?
Growing multi-microbial community on tooth surface embedded in a matrix of bacterial and salivary origin polymers.
Where does plaque occur?
Supragingivally and subgingivally, can develop between teeth and in the gingival crevice.
What is biofilm?
Thin layer of bacteria and other microorganisms.
What are the niches where biofilm adheres in the oral cavity?
- Saliva
- Dorsum of tongue
- Buccal/palatal epithelium
- Floor of mouth epithelium
- Supragingival hard tissue
- Subgingival hard tissue
What organic materials are found in the intracellular matrix of plaque?
- Polysaccharides
- Lipids
- DNA
- Proteins
- Glycoproteins
What inorganic materials are found in the intracellular matrix of plaque?
- Calcium ions
- Phosphorous ions
- Sodium, potassium, fluoride ions (trace amounts)
What is calculus in relation to plaque?
Plaque + calcium ions.
What is the first step in plaque formation?
Pellicle Formation.
What does the organic pellicle layer consist of?
- Proteins
- Peptides
- Glycoproteins
What happens during the initial adhesion of bacteria?
Toothbrushing removes most pellicle, recolonization occurs almost immediately.
Who are the primary colonizers in plaque formation?
- Streptococcus
- Haemophilus spp.
- Neisseria spp.
- Actinomyces spp.
- Veillonella spp.
What occurs during colonization and plaque maturation?
Primary colonizers provide receptors for adhesion of other bacteria, leading to mature biofilm.
Who are the secondary colonizers in plaque maturation?
- Prevotella intermedia
- Prevotella loescheii
- Capnocytophaga spp.
- Fusobacterium nucleatum
- P. gingivalis
What are the three adaptive roles of biofilm?
- Protection
- Nutrition
- Physiochemical environment
What does the ecological plaque hypothesis state?
Change in environmental factors triggers a shift in resistant plaque microflora.
What can trigger a shift in plaque microflora according to the ecological plaque hypothesis?
- Change in pH
- Temperature
- Oxygen levels
True or False: Plaque-induced diseases are caused by specific bacteria.
False.
What leads to heterogenicity and pathogenicity in plaque maturation?
Shift from early aerobic Gram + to mature anaerobic Gram -.
