Test 4: Normal Oral Microbiota Flashcards
What makes the oral cavity a hospitable place for microbes?
-warm, moist, constant source of nutrition
What are the 3 ecological niches provided by the human host?
- dorsum of tongue
- clinical crowns of teeth
- gingival sulcus
Which niche has the lowest concentration of organisms and what is its concentration?
Dorsum of tongue
-7.5*10^8/mL saliva
Which niche is the most aerobic?
Dorsum of tongue
Which niche provides the most different types of substrates for bacterial attachment?
Gingival sulcus: hard and soft tissue
What niche is the most anaerobic?
Gingival sulcus
What type of inter-species interaction increases the diversity of organisms?
Neutral and Cooperative/beneficial
Which inter-species interaction limits colonization of systemic pathogens?
Antagonistic/inhibitory
Which method of identification gives the largest number of organisms?
Total Count: includes both live and dead organisms
Which method of identification is the best for identifying different organisms?
Analysis of 16s ribosomal subunits (DNA sequencing)
In what groups of people are stable organisms found?
Adults with at least some anterior and posterior teeth (not young people or old edentulous people)
What is one of the first organisms to colonize after birth?
Streptococcus salivarius
What medium is used to grow oral streptococci?
Mitus-salivarius
What type of hemolysis mechanism to most streptococci use?
Alpha-hemolysis
Which microbes are considered systemic pathogens? **
- Strep sanguis
- Staph aureus
- Peptostreptococcus anaerobius
- Neisseria gonorrhoeae
- Acintomyces israelli
- Candida Albicans
Where is strep salivarius predominantly found?
- makes up 50% of count from dorsum of tongue
- soft tissue
Where is strep sanguis predominantly found?
Supragingival plaque
What systemic disease is srep sanguis associated with?
Infective Endocarditis
Which oral streptococci is cariogenic?
Strep mutans; aciduric and acidogenic
What does staph aureus commonly cause?
Osteomyelitis
Where in the oral cavity can peptostreptococcus anaerobius be found?
- gingival sulcus, infected pulp, dental abscesses
- obligate anaerobe
What systemic disease is assocaited with peptostreptococcus anaerobius?
Ludwigs angina (enlargement and swelling of neck from cellular infiltrate)
What are the most populous groups in the oral cavity?
Oral Strep and Veillonella parvula
What type of relationship does veillonella parvula have with strep mutans?
Beneficial: VP can’t ferment carbs because they lack the kinases, require intermediate metabolites created by strep mutans
