Normal Oral Microflora Flashcards
What is the oral microflora?
The microorganisms that reside in the oral cavity
What type of relationship does the normal oral microflora have with the body?
Commensalism
Why is it difficult for pathogens to colonize in the oral cavity?
The normal microflora compete for limited space and nutrients
What type of bacteria is primarily supragingival?
Streptococci
Is Actinomyces gram positive or negative?
Positive
Is Streptococci gram positive or negative?
Positive
Is Prevotella gram positive or negative?
Negative
Is Porphyromonas gram positive or negative?
Negative
Is Fusobacterium gram positive or negative?
Negative
Is Fusobacterium gram positive or negative?
Negative
Is Veillonella gram positive or negative?
Negative
What type of aerobe is Streptococci?
Facultative anaerobe
What are the five types of subgingival bacteria?
- Actinomyces
- Prevotella
- Porphyromonas
- Fusobacterium
- Vellionella
APPFV
What are the four Streptococci groups?
- Mutans
- Salivarius
- Mitis
- Angiosus
What shape is Streptococci?
Cocci
What color are Streptococci viridian colonies on blood agar?
Green
What pathology does the S. mutans group cause?
Dental caries
What do S. mutans produce?
Acid, causes low pH
What is S. mutans virulence property?
Ability to form biofilm
What is the primary pathogen in causing dental caries?
S. mutans
Where is Salivarius group found in the oral cavity?
Mucosal surfaces, including the tongue
Where does S. mutans colonize at in the oral cavity?
Tooth or denture surfaces
Is S. salivarius an opportunistic, primary pathogen, or part of the normal flora?
Opportunistic
Is S. vestibularis an opportunistic, primary pathogen, or part of the normal flora?
Normal flora
What are the two bacteria in the Salivarius group?
- S. salivarius
- S. vestibularis
What four bacteria are in the Mitis group?
- S. sanguinis
- S. gordonii
- S. mitis
- S. oralis
SGMO
What group are the early colonizers in biofilm formation?
Mitis group
What group (primarily speaking) can become an opportunistic pathogen and cause infective endocarditis?
Mitis group
What group is primarily ground in plaque formation and mucosal surfaces?
Anginosus group
Is the Anginosus group a primary or opportunistic pathogen?
Opportunistic
What group is involved in maxillofacial infections?
Anginosus group
What are the three bacterium in the Anginosus group?
- S. anginosus
- S. intermedius
- S. constellates
AIC
What are four features of gram positive bacilli?
- Purple stain
- Thick peptodiglycan layer
- No LPS layer
- No outer layer
What bacilli bacterium is involved in caries formation?
Lactobacilli
What pH range does Lactobacilli grow in?
Acidogenic and acid tolerant
What shape is pleomorphic bacteria?
No distinct shape, can also be changing shape
What shape is eubacteria?
Pleomorphic
Where are Eubacteria found primarily?
Dental plaque, specifically in periodontal pockets
What type of aerobes are Eubacteria?
Obligate anaerobes
What type of aerobes are Propionibacterium?
Strict anaerobes
Where is Propionibacterium found?
Dental plaque
Where are Actinomyces species found?
Major component of dental plaque, found in subgingival microbiota of healthy individuals
Can Actinomyces be a primary or opportunistic a pathogen?
Opportunistic
What is acinomycosis?
Abcesses, chronic inflammation in the orofacial region
What are four features of gram-negative bacteria?
- Pink stain
- Outer layer
- LPS
- Small layer of peptiglycogan
What type of aerobe are the Veillonella species?
Anaerobic
Is the Veillonella species gram positive or negative?
Negative
Where is the Veillonella species found?
Dental plaque
What bacterium is associated with aggressive periodontitis?
Aggregatibacter actinomycetemcomitans (AA)
What is a key bridging organism between the early colonizers and periodontal pathogens?
Fusobacterium species
Where are Fusobacterium species found?
Low numbers in healthy subgingival biofilm, enriched in pockets
What are the two types of Porphyromonas bacterium?
- P. gingivalis
- P. endodontalis
What type of Porphyromonas is found in infected root canals?
P. endodontalis
What type of Porphyromonas is found in advanced periodontal lesions?
P. gingivalis
What type of bacterium is associated with periodontitis and endodontic infections?
Prevotella intermedia
What is Campylobacter rectus a causative agent of?
Chronic periodontal disease
What type of aerobe is Campylobacter rectus?
Strict anaerobe
What type of aerobe is Treponema?
Struct anaerobe
What is Treponema associated with?
Progression of periodontal disease
If gram negative bacteria, then what opportunistic pathogen can increase?
Fungi
What virus is most commonly found in the saliva and orofacial region and is the causative agent of cold sores?
Herpes simplex virus type 1
What four factors can contribute to disease?
- Salivary flow rate
- Diet
- tobacco use
- Integrity of the immune system
What does Tanerella forsythia cause?
Connective tissue destruction and alveolar bone resorption in periodontal disease
What type of bacteria is Tanerella forsythia?
Gram negative anaerobe
What is the most abundant type of fungi in the mouth?
Candida species
What causes an increase likelihood of getting oral thrush/Candida overgrowth?
Dentures and orthodontic appliances
What part of the mouth is environmentally suitable for gram negative obligate anaerobic bacteria that are involved in periodontal disease and halitosis?
Dorsum of the tongue
What pH range is saliva typically between?
6.75 and 7.25
What can gingival crevicular fluid do?
Remove non-adherent bacteria, introduce IgG and neutrophils, and provide peptides and carbohydrates that bacteria can use for metabolism
