DOH133 Lecture Notes - Lecture 6: Asepsis, Commensalism, Coevolution
Describe each of the phases of biofilm formation
1. Pellicle formation
Oral bacteria attach to pellicle
2. Transport
Microbes approach tooth via salivary flow
3. Long-range interactions
Balance between Van der Waals forces and electrostatic repulsion
4. Short-range interactions
Stereochemical reactions
5. Cooaggregation/coadhesion
New microbes attach to the first generation of cells
6. Biofilm Formation
Process continues, confluent growth and increased complexity
7. Detachment
Question: Write down one reason which suggests Lactobacillus are not involved in
initiation of
cariogenic lesions
Caries lesions can develop in the absence of lactobacilli
May have to do with Lactobacilli’s ability to attach to the enamel – this process is
unknown
Lactobacilli is a facultative anaerobe – makes ATP by aerobic respiration or anaerobic
respiration
What class of chemicals does chlorhexidine fall into?
Bisguanide – damaging the cells membrane of the bacteria with resultant egress of the
cell components
List two physical characteristics of the bleeding pockets that influence the
species of bacteria able to occupy this niche
Blood – Beta haemolysis represents a complete breakdown of the haemoglobin of the
red blood cells in the vicinity of a bacterial colony – staphylococcus aureus
Pockets – allow for the accumulation of anaerobic bacteria
Name a gram negative rod found in active pockets of periodontitis
Prophyromonas Gingivalis
Infection control procedure
Patient evaluation
Personal protection
Document Summary
Describe each of the phases of biofilm formation: pellicle formation. Microbes approach tooth via salivary flow: long-range interactions. Balance between van der waals forces and electrostatic repulsion: short-range interactions. New microbes attach to the first generation of cells: biofilm formation. Process continues, confluent growth and increased complexity: detachment. Question: write down one reason which suggests lactobacillus are not involved in initiation of cariogenic lesions. Caries lesions can develop in the absence of lactobacilli. May have to do with lactobacilli"s ability to attach to the enamel this process is unknown. Lactobacilli is a facultative anaerobe makes atp by aerobic respiration or anaerobic respiration. Bisguanide damaging the cells membrane of the bacteria with resultant egress of the cell components. List two physical characteristics of the bleeding pockets that influence the species of bacteria able to occupy this niche. Blood beta haemolysis represents a complete breakdown of the haemoglobin of the red blood cells in the vicinity of a bacterial colony staphylococcus aureus.
