Lecture 4 questions

Question 1

have we been able to culture over 60% of our oral species?

Answer 1

no

Question 2

what is a plaque biofilm?

Answer 2

organized cooperating community of organisms with specific inter-bacterial and host-bacterial interactions

Question 3

describe how a biofilm forms?

Answer 3

1. salivary glycoproteins and antibodies in the pellicle form a layer in the first 2 mins, which creates an abiotic surface
2. bacteria that attach vary in attachment ability
   a. rapid attachers that have specific attachment structures like fimrbiae, etc
   b. slow attachers that have no specific mechanisms
   c. our model organisms are Ss(Strep sanguis) and Av ( (Actinomyces viscosus)
3. bacterial characteristics change after attachment, bacteria will divide and multiply and within 30 minutes you have a new micro biome protecting your teeth
4. co-aggragation happens in solution in giant clumps, which then attach to pellicle. This is cell-to-cell recognition of genetically distinct cell types
   a. F. nuc coaggragates with S. cristatus
5. co-adhesion happens between suspended and already adhering microorganisms, influenced by temp and lactose levels (high temp and high lactose –> no/low adhesion)
6. maturation involves inc in diversity, replication and matrix formation (immediate formation of capsule) and ecological succession

Question 4

which are the most dangerous colonizers?

Answer 4

tertiary (slow attachers)

Question 5

What is F. nuc?

Answer 5

a secondary colonizer, a robust anaerobe, a bridge organism. As long as its levels are low, we can keep the tertiary colonizers at bay

Question 6

do you get periodontist from having gingivitis?

Answer 6

not always, but gingivitis gets you closer to getting periodontitis after a few times

Question 7

what are characteristics of a healthy oral system?

Answer 7

aerobic, breaks down small carbs, and uses oxidative phosphorylation