Oral Cavity Microbiology

  1. Gram positive cocci that is catalase negative?
  2. Gram positive cocci that is catalase positive?
  3. Viridans strep is ____ hemolytic. Optochin ___, and bile ____.
    • Alpha
    • Non-sensitive
    • Insoluble
  4. Virulence factors for viridian strep:
    • Adhesins
    • Produce dextrans
    • Biofilms
  5. Which microbe is responsible for initiating events in dental caries?
    Viridan strep
  6. Gram positive nonfilamentous non-endospore formers?
  7. Gram positive filamentous non-endospore former?
    Actinomyces israelii
  8. Gram negative rods?
    Bacteroides, Fusobacterium
  9. True/false: lactobacillus is part of normal microbiota of the mouth, stomach, intestines and GU
  10. Which of the oral cavity microbe is acidophilic?
  11. Lactobacillus major fermentation product is___?
    Lactic acid
  12. True/false: some strains of lactobacillus makes H2O2
  13. What does H2O2 (hydrogen peroxide) inhibit?
    Inhibit anaerobes an other bugs without catalase
  14. True/false: Viridan strep is involved with progression of caries
    False; they are involved in initiation of caries while LACTOBACILLUS is involved with PROGRESSION of caries
  15. Which oral cavity microbes are aerotolerant anaerobes? And what does that mean?
    • Bacteroides and Fusobacterium
    • Means they don’t use oxygen in its metabolism but can survive with or without oxygen
  16. Fusobacterium and bacteroides are usually superoxide dismutase ______ or catalase _____
    • Positive
    • Positive
  17. What are virulence factors for Gram negative aerotolerant anaerobic bacilli in the mouth, colon, and GU?
    • LPS (because Gr -)
    • Adhesins
    • Capsules (some)
    • Collagenase
    • Neuraminidase
    • Deoxyribonuclease, heparinase, proteinase
  18. Aerotolerant anaerobe growth is stimulated by ____, and they are bile-esculin ____
    • Bile
    • Positive
  19. True/false: most strains of Viridan strep synthesizes beta lactamases
    False; Strep are Gr+, why would they have beta lactamases. Bacteroides synthesize beta lactamases
  20. What can Bacteroides cause in the colon?
    Polymicrobial intraabdominal abscesses, peritonitis
  21. Do bacteroides have capsule?
    Yes. Their capsule can stimulate abscess formation and can turn them on or off to avoid immune system
  22. Which microbe is the bridging bacterium in plaque?
  23. Which microbe is the most common anaerobe in advanced periodontal disease?
  24. Bacteroides are Gr- _____ rod, Fusobacterium is Gr- ___ rod (morphology)
    • Pleomorphic
    • Long, tapered
  25. Which microbe has characteristic “molar tooth colonies”?
    Actinomyces isarelii
  26. Is Actinomyces acid fast?
    Nope, they are non-acid fast
  27. What is characteristic of the actinomycosis pus?
    Sulfur appearance granules (does NOT contain sulfur)
  28. What are the three common forms actinomycosis?
    • Cervicofascial
    • Thoracic
    • Abdominal
  29. How is actinomyces introduced to cause cerviofascial actinomycosis?
    Through trauma, introduced into mucosa
  30. True/false: Candida albican is dimorphic, germ tube positive and azole resistant
    False; it is dimorphic and germ tube positive but sensitive to azole
  31. In dehydrated state, does the bacterial content in the saliva increase or decrease?
  32. Are thre more aerobes or anaerobes in the mouth and where do they live in the mouth?
    more anaerobes and they are in the gingival crevices
  33. Gingival crevice has more anaerobe than aerobes, just like which other anatomical site?
    • colon
    • 1000:1 anaerobe to aerobe ratio
  34. True/false: tooth surface and saliva have approximately the same anaerobe to aerobe ratio
    True, 1:1 ratio
  35. True/false: most bacterial causes of periodontal disease are acquired bacteria from the environment
    False; they are usually normal microbiota anaerobes
  36. What type of bacteria (Gr+ / Gr-) are involved in gingivitis?
    Gr- AND Gr+ anaerobes
  37. What are common causative agents for periodontal abscess?
    • Gr- rods
    • Streo viridans
    • Anaerobic streptococci
  38. What are common causative agents for Ludwig angina?
    • Streptococcus
    • Bateroides
    • Fusobacterium
  39. What are common causative agents for osteomyelitis of the jaw?
    • Gr – rods
    • Anaerobic streptococci
    • Actinomyces israelii
  40. What is Ludwig angina?
    Progressive cellulitis, infection of soft tissues surrounding the oral cavity and can cause death due to asphyxiation
  41. What are common clinical presentations of oropharyngeal Candida albicans?
    • Pseudomembranous white plaques
    • Erythematous
    • Angular chelitis – painful fissuring at corners of mouth
  42. True/false: candida albicans can cause esophagitis
  43. What is the progression of dental caries?
    Attachment, Dextran production, Acid production, Proteolysis, maturation
  44. Which microbe has drainage fluid that resemble grain of sulfur?
Card Set
Oral Cavity Microbiology
GI Final- Microbiology