properties and formation of dental plaque :)

Question 1

what is plaque

Answer 1

biofilm mixture of different species of bacteria embedded in a matrix of polymers

Question 2

what is a microbiome

Answer 2

all the bacteria in the body

Question 3

what is an oral microbiome

Answer 3

all the bacteria in the oral cavity

Question 4

where can micro biome be found in babies not born

Answer 4

in amniotic fluid

rupture to membrane can mean that bacteria can enter the placenta

Question 5

post natal acquisition of oral flora

Answer 5

normal delivery

c section

Question 6

what does the micro biome reflect from normal delivery

Answer 6

vaginal tract microbiota

e.g. lactobacillus

Question 7

what does the micro biome reflect through c section

Answer 7

skin microbiiota

e.g. staphylococcus

Question 8

what does breast feeding affect

Answer 8

more lactobacillus may reduce candida levels

Question 9

most common colonisation from mother to child

Answer 9

streptococcus saliarius

Question 10

colonisation sites in the mouth

Answer 10

teeth tongue
cheeks, lips, saliva
orthodontic saliva
implants
dentures

Question 11

what is dental disease caused by

Answer 11

mix of species of bacteria working together

Question 12

formation of plaque biofilm steps

Answer 12

host surface adhesion
host surface adhesion (specific)
inter bacterial adhesion
growth and multiplication

Question 13

describe the first host surface adhesion

Answer 13

reversible

physio-chemicla interactions

Question 14

describe the second host surface adhersion

Answer 14

irreversible

specific molecular interctions

Question 15

interbacterial adhesion

Answer 15

co aggregation

Question 16

how do bacteria adhere to the tooth

Answer 16

through the acquirred pellicle

Question 17

what is the pellicle on the tooth

Answer 17

layer of selectively absorbed salivary protiens

forms on the surface enamel

Question 18

what is found in the pellicle

Answer 18

proline rich protien
mucins
statherian

Question 19

what are the adhesion mechanisms

Answer 19

electrostatis
protein carbohydrate/protien-protein
polymer bridging

Question 20

what are glycoprotiens

Answer 20

sugar chains linked by N/O glycosylation to mucins

Question 21

how can bacteria be attached to glycoprotiens

Answer 21

by lectins (lectins target is a sugar on another molecule)

Question 22

what are cryptitiopes

Answer 22

hidden receptors for bacteial adhesion

Question 23

how can species of bacteria help each other

Answer 23

one uses proteins to remove the sugar exposing the cryptitiope so the other can attach to the exposed region

Question 24

what is it called when bacteria adhere to each other

Answer 24

co aggregation

Question 25

what does coaggregation of bacteria involve

Answer 25

``` surface appendages (fimbria or fibrils) fibrils can grab sugar or protien so the bactiera can stick down ```

Question 26

how can a microbiome build up

Answer 26

bacteria can aggreagate between them bind to acid of mucins bind to polysaccharides or surface protiens

Question 27

sources of nutrition for plaque

Answer 27

salivery glycoprotiens salivery protiens urea

Question 28

how does ph vary in plaque

Answer 28

pH lower in lower bifilm

Question 29

how does salivery nutriens vary in biofilm

Answer 29

higher closer to top

Question 30

where do aerobic species prefer in the biofilm

Answer 30

top

Question 31

what do gradients in the plaque lead to

Answer 31

different niches

Question 32

what do autoinducers do

Answer 32

signal to increase the density of bacteria where bacteria are most beneficial

Question 33

what can bacteria sense

Answer 33

population numbers influencing behavior

Question 34

what happens at high cell density

Answer 34

high autoinducer | leads to transcription of target gene

Question 35

what happens at low cell density

Answer 35

low autoinducer | no transcription of target gene

Question 36

what is calculus

Answer 36

calcified plaque matrix and bacteria

Question 37

how does calculus form

Answer 37

increase in pH, Ca and phosphate | mineral growth around bacteria

Question 38

limitations to plaque deveolping

Answer 38

salivary flow gingival crevicular fluid antibacterial substances

Question 39

antibacterial substances

Answer 39

lysosome (breaks down cell walls) lactoferrin (limits and binds iron) sialoperoxidase (attack bacteria) aggreagating factor (stop bacteria attatching to surface)

Question 40

progression of plaque formation steps

Answer 40

``` primary adherer metabolism changes environment bacterial succession climax community ```

Question 41

colonisation sites in the mouth

Answer 41

``` teeth tongue cheeks/lips/palate orthdontic appliances implants dentures ```

Question 42

teeth niche

Answer 42

calciumhydroxyapitite mineral stagnation sites have less saliva flow food source from ofood

Question 43

tongue niche

Answer 43

lots of niches due to irregular surface

Question 44

cheeks/lips/saliva niche

Answer 44

more saliva present micro biome more stable, less diverse dominated by streptococcus

Question 45

denture niche

Answer 45

favours fungal growth

Question 46

how to cryotitopes become exposed

Answer 46

``` adsorption to the tooth enzymic alteration (protease/glucosidase action) ```

Question 47

building up of a micro biome coloniser

Answer 47

actinomyces selectively bind tostatherin and PRPs strep. sanguimis binds to silica acid of mucisn strep. mutans binds to PRPs and mucin like glycoprotein

Question 48

inter bacterial substaces

Answer 48

salivary material bacterial exopolysaccharides bacterial surface structres

Question 49

what can components of interbacteral substances do

Answer 49

adsorb to bacterial surfaces precipitate from solution chemical change pH

Question 50

what does quorum sensing and autoinducers do

Answer 50

allow coordination of behaviour - biofilm formation - virulence factor producion - bioluminesense