2 - ORAL MICROBIOLOGY

What colors are the early colonizers?

- Blue

- Purple

- Green

- Yellow

What colors are the secondary colonizers?

Orange and Red

What are the BLUE species?

A. viscosus and A. naeslundii

What is the PURPLE species?

A. odontolyticus

What are the GREEN species?

E. corrodens and Aa

What are the YELLOW species?

- S. mitis

- S. oralis

- S. sanguis

What are the ORANGE species?

- Fusobacterium

- P. intermedia

- Campylobacter

What are the RED species?

- P. gingivalis

- T. forsythia

- T. denticola

Which complex of periodontal microbes is associated with periodontal health?

Purple

Which complex of periodontal microbes is associated with gingivitis?

Yellow

Which complex of periodontal microbes is associated with deeper pocket depth?

Orange and Red

Which complex of periodontal microbes is associated with BOP, inflammation and destructive periodontal disease?

Red

What is the two common dental infections?

Caries and periodontal diseases

Where are some niches that plague may be found?

- Intraoral and supragingival hard surfaces i.e. teeth and implants

- Periodontal pockets

- Dorsum of tongue, saliva

- Buccal mucosa, palatal epithelium, tonsils

What are some ways to remove microbes from oropharynx?

- Swallowing, mastication, or blowing nose

- Oral hygiene practices

- Effects of saliva

- Active motion of cilia

What are structured resilient yellow=grayish substance that adheres tenaciously to intraoral hard surfaces?

Dental plague

What is a well-organized heterogenous structure for cooperating community of microorganisms?

Biofilm

What does dental plaque form?

Biofilm

TRUE or FALSE

Deeper periodontal pockets have less microbes

FALSE

Answer: more

What is the most prevalent species of fungi found in the oral cavity?

Candida albicans

C. albicans infections are prevalent among?

Denture wearers and aging people

TRUE or FALSE

Only bacteria is found in the oral cavity

FALSE

Answer: also fungi, yeasts, protozoa, viruses

What are some of the virus-related oral diseases?

- Herpesviruses

- Human papillomaviruses

- Picornaviruses

- Retroviruses

Herpes simplex virus-1, herpes simplex virus-2, varicella-zoster virus, Epstein-Barr virus, etc. are categorized under?

Herpesviruses

Which disease can induce benign lesions of the skin (warts) and mucous membranes (condylomas) and can cause epithelia malignancies (cancer)?

Human papillomaviruses

Poliovirus, hepatitis A virus, rhinovirus, and enteroviruses are categorized under?

Picornaviruses

HIV-1 and HIV-2 is categorized under?

Retroviruses

Bacteria exist and proliferate within an?

Intracellular matrix

Matrix functions as a _____

barrier

TRUE or FALSE

Some dental plague may be innocuous (harmless and beneficial)

TRUE

What are the classifications of dental plague?

- Supragingival

- Subgingival

- Marginal

Which type of plague is composed of gram positive cocci, short rods and is predominately at the tooth surface?

Supragingival plague

Which species are associated with supragingival plague?

- S. sanguis

- Actinomyces viscosus

- S. mitis

- A. naeslundi

- Eubacterium species

Which type of plague is associated with a biofilm that develops on the tooth surface coronal to the gingival margin?

Supragingival plague

What is associated with calculus and root caries?

Supragingival plague

What occurs when supragingival plaque is in direct contact with the gingival margin?

Marginal plaque

What is associated with the development of gingivitis?

Marginal plaque

Which type of plague is associated with a biofilm that develops on tooth surface apical to the gingival margin?

Subgingival plaque

How many days does it take biofilm to reform after mechanical disruption?

2-3 days

Biofilm can be _____ disrupted

Subgingival plague is associated with what disease?

Periodontitis

Gram negative rods, cocci, filaments. flagellated rods, spirochetes are found on the outer surface of _____ plaque

subgingival

Bacteria associated with subgingival plague are located in _____ environment

anaerobic

TRUE or FALSE

The composition of bacteria found in plague are all the same

FALSE

What is the most common colonizer (species of bacteria) for subgingival plague?

- P. gingivalis

- T. forsythia

Composition of subgingival plague depends on?

Pocket depth

TRUE or FALSE

Plague is visibly seen after 1-2 days of no oral hygiene

TRUE

Where is dental plaque found heaviest?

Gingival/cervical third

What is found on all surfaces of the oral cavity and functions as a protective barrier, providing lubrication, preventing desiccation, as well as a substrate to which bacteria attach?

Pellicles

What are some gram positive facultative microbes that are associated with primary colonization?

- Actinomyces viscosus

- Streptococcus sanguis

Gram positive bacteria adhere via adhesions to?

Pellicle

As plague matures there is a shift in the biofilm from gram positive facultative to?

Gram negative anaerobes

Primary colonization is associated with?

- Gram positive facultative microbes

- Attachment to pellicle

What are some bacteria species associated with secondary colonization?

- P. gingivalis

- T. forsythia

- T. denticola

Gram positive cocci and short rods are seen in _____ plague formation

early

Gram negative, anaerobic rods and filaments, spirochetes are seen in _____ plaque

mature

What formation describe the interactions between the microbes comprising the early and mature plague?

Corncob

What is the gold standard of microbial testing?

Bacterial culture

Susceptibility of microbes in testing is through the use of?

Antibiogram

What species has colony that are star-shaped?

A. actinomycetemcomitans

What are some testing methods for microbial diagnosis?

- Bacterial culture

- Dark field and Contrast microscopy

- Molecular biologic test

- Immunological test

- Genetic testing

Complexes of Periodontal Microbes

Early colonizers:

BLUE, PURPLE, GREEN, YELLOW

Secondary colonizers:

ORANGE, RED

What species is associated with periodontal health?

A. odontolyticus

What species are associated with gingivitis?

- S. mitis

- S. oralis

- S. sanguis

What species are associated with deeper pocket depth?

- Fusobacterium

- P. intermedia

- Campylobacter

P. intermedia is always found with?

F. nucleatum

What species are associated with bleeding on probing (BOP), clinical marker for inflammation, and destructive periodontal disease and periodontal pocket depth?

- P. gingivalis

- T. forsythia

-. T. denticola

What are virulence factors that allow for adhesion?

Fimbriae or pili

What function to degrade host extracellular proteins?

Trypsin-like proteases

What are multifunctional proteins that play a role in adhesion, tissue degradation, and evasion?

Gingipains

Trypsin-like proteases are produced by?

- P. gingivalis

- T. denticola

- T. forsythia

Proteases and leukotoxin are produced by?

A. actinomycetemcomitans

What are associated with localized aggressive periodontitis?

Hyperleukotoxic strains of A. actinomycetemcomitans

What are produced by the microbes and act on the intercellular substance of sulcular epithelium, collagen fibers and the ground substance of connective tissue?

Enzyme

What metabolites do microbes use?

Carbohydrates, amino acids, and proteins

What contributes to inflammation by inducing phagocytosis and chemotaxis of neutrophils?

Endotoxin (LPS)

What stimulates bone resorption and is highly associated with Pg?

Endotoxin (LPS)

Microbes products and surface antigens that penetrate into the periodontal tissues initiate?

Inflammatory response

LPS endotoxin, proteases, collagenase are associated with?

Porphyromonas gingivalis (Pg)

Leukotoxin is the key to virulence and pathogenicity for?

A. actinomycetemcomitans (Aa)

Endotoxin (LPS) is highly associated with which species of bacteria?

Pg

What type of Aa is considered most virulent?

Serotype b

TRUE or FALSE

All plague are alike

FALSE

All plague are not equally capable of causing disease

TRUE

Capsule in bacteria function ot?

Evade host immunity

What is an infection called where many species are present?

Polymicrobial infection

Working together is also known as?

Synergy

Imbalance is also known as?

Dysbiosis

Polymicrobial infection initiate a microbial imbalance or dysbiosis result in?

Inflammation and periodontal disease

What are the keystone pathogens that elevates the virulence of the entire bacterial colony?

Pg and Aa

What species impairs host immunity and protective mechanisms?

Pg

Treatment is aimed at reducing inflammation that may shift dysbiosis back to a state of?

Healthy homeostasis

TRUE or FALSE

There are beneficial microbes in the oral cavity

TRUE

TRUE or FALSE

S. sanguis produces H2O2 that kills Aa

TRUE

Periodontal disease results from the "elaboration of noxious products by the entire plaque flora". This is known as?

Nonspecific plaque hypothesis

TRUE or FALSE

The host can easily neutralize small amounts of plague products

TRUE

TRUE or FALSE

The more plaque present, the more virulent factors present, the more inflammation and destruction, the greater the manifestation of clinical disease

TRUE

TRUE or FALSE

The more plaque the more severe the inflammatory response

TRUE

Control of periodontal disease is dependent upon controlling the amount of _____ accumulated

plaque

When oral hygiene resumed, with the removal of accumulated plaque, marginal gingivitis resolved within _____ days

seven