Commensal and Pathogenic Microorganisms

Question 1

What kind of infection is candida infection?

Answer 1

Candida is an opportunistic infection.

Question 2

What are the 5 signs of inflammation?

Answer 2

Local hyperthermia, fever

Hyperemia (redness)

Tissue swelling

Burning pain

Functional impairment

Question 3

How common are infectious disease deaths?

Answer 3

> 10 million deaths annually

Most occur in children especially from resp and diarrhoeal infections

US 2 of the top 10 causes of death are infectious.

Question 4

What are the classifications of infectious?

Answer 4

According to clinical appearance

Question 5

What are the types of infections according to clinical appearance?

Answer 5

Acute infections

Chronic infections

Acute exacerbation of chronic infection

Question 6

What are eg of types of infection based on etiological agent?

Answer 6

Bacterial

Viral

Fungal

Parasitic

Question 7

What are eg of types of infection based on source of infection?

Answer 7

Odontogenic

Secondary infections of lesions such as cyst or tumours

Infections that arise from contaminated wound or trauma

Iatrogenic infections

Question 8

Why are commensal microflora so important?

Answer 8

1/10 cells in our body are human cells

They protect our body from invasion by pathogenic microorganisms

Question 9

Where is oral microflora located?

Answer 9

Oral biofilm covers teeth, mucosal surfaces, and the gingival sulcus

Question 10

What is the oral microflora composed of?

Answer 10

Aerobic gram-positive cocci

Anaerobic gram-positive cocci

Anaerobic gram-negative rods

Question 11

What kind of relationship is there between human and oral microflora?

Answer 11

Mutualism

Question 12

What kind of microbial organisms are present in the gingival crevice/pocket?

Answer 12

In health, aerobic. In disease, anaerobic

Question 13

What factors affect the growth of microorganisms in the oral cavity?

Answer 13

Temperature

pH

Nutrients

Host defenses

Host genetics

Antimicrobial agents and inhibitors

Question 14

What life changes influence the oral microflora?

Answer 14

Loss of teeth

Age

Eruption of teeth

Dentures

Question 15

Why are streptococci very cariogenic?

Answer 15

They can grow on hard tissue

Question 16

Which streptococci are associated most with endocarditis?

Answer 16

In order of most common to least common:

S. mitior

S. sanguis

S. mutans

Question 17

Which oral streptococci are associated most with endocarditis?

Answer 17

In order of most common to least common:

S. mitior

S. sanguis

S. mutans

Question 18

Which streptococci are most cariogenic?

Answer 18

S. mutans > S. sanguis > S.mitior

Question 19

What changes occur to oral microbiota during disease?

Answer 19

Fungal-bacterial dysbiosis

Altered PRR, TLR, NOD-like, C-type lectin receptor expression

Candida invasion

Epithelial damage

Question 20

What causes odontogenic infections?

Answer 20

Odontogenic infections arise from teeth and have a characteristic flora. They arise from indigenous bacteria that normally live on the host.

They are often initiated by caries, periodontal disease, and pulpitis and spread beyond teeth to the alveolar process and to the deeper tissues of the face, oral cavity, head, and neck

Question 21

Which bacterial species are likely to cause odontogenic infections?

Answer 21

5 main species that are likely to cause infection.

Question 22

How should odontogenic infections be treated?

Answer 22

Broad spectrum antibiotics such as Amoxycillin

Question 23

How does bacterial composition differ by type of infection?

Answer 23

Early infections appearing as a cellulitis are predominantly aerobic streptococcal infections. Oedema is a sign of aerobic

Late, chronic abscesses may be characterized as anaerobic infections

Question 24

What are the types of odontogenic infections?

Answer 24

Periapical (starting from a periapical abscess)

Periodontal (Starting from a periodontal pocket or from pericoronitis)

Question 25

Where does the infection typically go following a periapical infection?

Answer 25

Infection erodes through the thinnest bone. (easiest pathway)

When the apex is below the attached muscle vestibular abscess results.

If apex is higher than muscle attachment, the adjacent fascial space is involved.

Question 26

What are the types of host defense mechanisms?

Answer 26

Local defenses: Intact anatomic barrier and indigenous bacteria

Humoral defenses: Immunoglobulins, and complement

Cellular defenses: Phagocytes and lymphocytes

Question 27

What are some causes of medical compromise in some patients?

Answer 27

Uncontrolled metabolic disease: Diabetes, alcoholism, and malnutrition

Suppressing disease: Leukaemia, lymphoma, and malignancy

Suppressing drugs: Chemotherapeutic agents, and immunosuppressives

Question 28

What is tubercolosis?

Answer 28

A chronic granulomatous disease caused by various strains of mycobacteria usually seen in humans.

Question 29

How common is TB?

Answer 29

nearly 8.6 million infected with TB disease

Increased in prevalence due to multi-drug resistant tubercolosis

Question 30

What are the oral manifestations in tubercolosis?

Answer 30

0.5 - 1% of all TB patients show them

Saliva is very contagious

Lesions form on oral mucosa.

Cervical lymphadenopathy: Tender, irregular, and enlarged.

Question 31

What are the measures of immune system reaction in TB?

Answer 31

Erythrocyte sedimentation rate

WBC count

Differential WBC count

Neutrophils

Basophils