mouth as microbial habitat

Question 1

distinct sites for colonisation

Answer 1

mucosal surfaces
teeth
saliva
GFC

Question 2

how do the microorganisms colonise?

Answer 2

-Variations in a tooth site as every site provides different environmental conditions

Question 3

Where is saliva produced?

Answer 3

-saliva produced by major subcarotid submandibular and sublingual glands as well as minor glands of oral mucosa

Question 4

what is saliva

Answer 4

host proteins/glycoprotiens
-flow rate, buffering role, host defences

Question 5

what is ginigival crevicular fluid?

Answer 5

serum-like exudate
-phagocytic
-host defences

Question 6

sites on teeth for bacterial colonisation

Answer 6

-smooth surface plaque
-approximal plaque
-fissure plaque
-gingival crevice plaque
-supra gingival plaque and subgingival plaque

Question 7

Temp (influencing colonisation and survival)

Answer 7

• within oral cavity usually constant 30-36, provides stable conditions for growth of microbes
  -when inflammation occurs, temp can rise up to 39

Question 8

Redox (influencing colonisation and survival)

Answer 8

-microbes display diff degrees of sensibility to temp and redox. Redox potential is ease it loses/gains electrons
-when loses its oxidised, when gains electron its reduced

Question 9

pH (influencing colonisation and survival)

Answer 9

-Microbes sensitive to extremes of acidity and alkali, prefer neutrality
-Mean ph for saliva is 6.75-7.25
-optimal for microbial growth
-after carb consumption, ph can fall rapidly due to acids after metabolism, then goes back to resting value. This depends on frequency of sugar intakes

Question 10

Nutrients (influencing colonisation and survival)

Answer 10

-many orgs nutritionally demanding, have specific requirements for growth
-in salvia-peptides, proteins vitamins considered endogenous nutrients
-exogenous nutrients come from our diet which we ingest, which are metabolised

Question 11

Host defences (influencing colonisation and survival)

Answer 11

-dependent on integrity of mucosa

Question 12

Host genetics (influencing colonisation and survival)

Answer 12

-some ethnic groups/gender affect microbiota

Question 13

Host lifestyle
(influencing colonisation and survival)

Answer 13

-diet, smoking, medication

Question 14

which type of immunoglobulins in saliva and GFC

Answer 14

-IgA in saliva,
-IgG, IgA, IgM in GFC

Question 15

e.g. of what in saliva

Answer 15

mucin/agglutinins, lysosome/protease/anion, lactoferrin, histatins, defensins

Question 16

e.g. of what in GFC

Answer 16

defensins, neutrophils, polymorphs

Question 17

physical mucosal defence

Answer 17

physical barrier

Question 18

immunological mucosal defence

Answer 18

presence of bacteria will induce on cells to release signalling molecules, in turn lead to reduction of bacterial load
-antigen presentation
-chemokine and cytokine signalling of PMNs

Question 19

why is mouth good microbial habitat

Answer 19

-warm, moist-extensive biofilm formation
-innate and adaptive host responses
-rich array of viruses, fungi, protozoa

Question 20

read last slide

Answer 20

read last slide