Oral Bacteria (Palmer)

Question 1

What are the conditions in the fissures and what bacteria are most prevalent there?

Answer 1

Nutrients: saliva and diet
pH: neutral - acidic
Redox: positive

Streptococcus

Question 2

What are the conditions in approximal surfaces and what bacteria are found there?

Answer 2

Nutrients: saliva, diet, GCF
pH: neutral - acidic
Redox: slight negative

Actinomyces

Question 3

What are the conditions in the gingival crevice and what bacteria is found there?

Answer 3

Nutrient: GCF
pH: Neutral - basic
Redox: Negative

Streptococcus and actinomyces

Question 4

What is the difference between the mitis group and mutans group of streptococci?

Answer 4

Mitis: sanguinis, gordonii, oralis; major species in plaque

Mutans: mutans, sobrinus; minor species in healthy plaque

Question 5

What bacterial species are the first to colonize the teeth?

Answer 5

Streptococci: bind to pellicle

Veillonella: metabolize lactic acid

Actinomyces: binds pellicle, and other colonizers

Question 6

Which species provides binding sites for late colonizers?

Answer 6

Streptococcus

Question 7

Which species inhibits strep mutans?

Answer 7

Streptococci

Question 8

What are the four virulence factors of strep mutans?

Answer 8

1. Acidogenic: metabolize carbs -> produce acid
2. Acid tolerant
3. Glycosyltransferases: form glucose polymers from sucrose
4. Glucan binding proteins

Question 9

Which bacteria make up the red complex?

Answer 9

1. P. Gingivalis
2. T. Forsythia
3. T. Denticola

*Periodontal disease

Question 10

What are the steps in developing periodontal disease?

Answer 10

Gingivitis (inflamed gums) -> build up of subgingival biofilms -> periodontitis