ICP3: Dental Plaque Flashcards
What are 4 of the general properties of biofilm?
- Protection (e.g. moisture, predators)
- Slow growth rate
- Get their physical characteristics from surface
- The variation of biofilm leads to their metabolic interactions
Define Dental Plaque
A complex microbial community on a tooth surface, embedded in a matrix of polymers of bacterial and salivary origin (BIOFILM)
Define biofilm
Biofilms are a collective of one or more types of microorganisms that can grow on many different surfaces
How are the properties of microorganisms growing in microfilm different to ones growing from planktonic growth? 2
- Microfilm grows slower
- Microfilm much more resistant to antimicrobial agents
Give 5 examples of synergistic interactions between organisms in a biofilm
- Enzyme sharing
- Food Chains
- Co- Adhesion
- Cell-to-cell signalling
- Gene transfer
Give 6 examples of antagonistic interactions between organisms in a biofilm
- Bacteriocin production
- H202 production
- Organic acid production
- Bacteriophage release
- Competition for nutrients
- Predation
Name 5 different types of dental plaque
- Fissure plaque
- Approximal plaque
- Gingival crevice plaque
- Denture Plaque
- Calculus
What are the 5 steps of the development of dental plaque
- Acquired enamel pellicle is deposited on clean tooth surface about 1µm thick
- Pioneer species of bacteria will adhere to the acquired pellicle
- Pioneering species multiply and form a confluent layer
- Accumulated bacterial growth leads to a decrease in oxygen tension which cultures anaerobic bacteria
- Plaque maturity
After brushing your teeth how long does it take for the acquired enamel pellicle to form?
2 Hours
What5 things is the acquired enamel pellicle composed of?
- Proteins
- Lipids
- Glycroproteins
- Saliva
- Gingival Crevicular fluid
What 4 components of the enamel pellicle are bacteria derived?
- Glycosyl Transferase
- Glucans
- Fructans
- Bacterial cell fragments
What 5 components of the enamel pellicle are host derived?
- Acidic, proline-rich proteins
- Amylase
- Lysozyme
- Albumin
- Immunoglobulins
What are the interactions that attract pioneer bacteria to the pellicle?
Van der Waals
What are the interactions that repel pioneer bacteria to the pellicle?
Electrostatic repulsion between negatively charged bacterial cell and pellicle surface
Explain the molecular interactions between bacteria and pellicle
Bacteriums have adhesive molecules that are complementary to the pellicle surface receptors