Oral Microflora

Question 1

What are 3 disease causing factors for caries? (BAD)

Answer 1

1-Bad bacteria
2-Absence of saliva
3-Dietary habits (poor)

Question 2

What are 4 protective factors for caries? (SAFE)

Answer 2

1-Saliva and Sealants
2-Antimicrobials
3-Fluoride
4-Effective diet

Question 3

Acquisition of oral strep and gram-negative species in children is predominantly from what source?

Answer 3

Their mothers

Question 4

What changes when teeth erupt?

Answer 4

There is now a non-shedding surface to which microflora can adhere

Question 5

What two bacteria generally only appear in the normal mouth following tooth eruption?

Answer 5

1-Streptococci Mutans

2-S. Sanguinis

Question 6

Dental plaque is a ______ but not all ________ are dental plaque

Answer 6

Biofilm, biofilms

Question 7

What are the 5 steps to dental biofilm development?

Answer 7

1-Pellicle formation (minutes to hours)
2-Attachment of a single bacterial cell (0-24 hr)
3-Growth of attached bacteria and formation of distinct micro colonies (4-24 hr)
4-Microbial succession w/increased diversity
5-Climax community/mature biofilm (~1 week)

Question 8

Salivary glycoproteins, phosphoproteins, lipids and some components of the gingival crevicular fluid make up what?

Answer 8

Pellicle

Question 9

What are 4 functions of the pellicle?

Answer 9

1-Protect tooth from acids
2-Matrix for enamel repair
3-Reduce friction
4-Receptor for lysosomes, immunoglobulins and other proteins

Question 10

What 3 species comprise 95% of the streptococci and 56% of total initial microflora?

Answer 10

1-S. Sanguinis
2-S. Oralis
3-S. mitis

*Mutans streptococcie comprise 2% or strep

Question 11

What process is exemplified by the shift from streptococcus dominant plaque to actinomyces dominated plaque?

Answer 11

microbial succession

*actinomyces implicated in root surface caries due to anaerobic

Question 12

Which hypothesis states that all plaque is bad and that the difference between caries and no caries is only the amount of plaque?

Answer 12

Non-specific plaque hypothesis

Question 13

Which hypothesis recognizes that plaque is a problem but the specific concentration of cariogenic bacteria is what is important?

Answer 13

Specific plaque hypothesis

Question 14

Which hypothesis states the disease-causing bacteria may be present in unaffected sites and that changes in local environment cause a shift in balance and result in demineralization?

Answer 14

Ecological plaque hypothesis

Question 15

How much saliva do we produce daily?

Answer 15

0.5-1.0 liters (99% water, less than 1% solids)

Question 16

What are 4 functions of saliva?

Answer 16

1-Inhibition of some bacteria
2-dilution and elimination of bacteria and their substrates
3-buffering bacterial acids
4-Reparative environment