Microbio Module 10

Front 1

describe what is required for stable colonization once oral microbes enter the mouth

Back 1

Stable colonization requires continual attachment, growth, and generation of
daughter cells that detach and must re-adhere to freshly exposed epithelial cells.

Front 2

Question 2: name 2 predominant species that colonise the tongue

Back 2

Streptococcus mitis
S. salivarius

Front 3

Question 3: briefly describe why saliva both hinders and helps microbial colonization of the oral mucosa

Back 3

aid bacterial adherence, and molecules in saliva that act as carbon and nitrogen sources for bacteria assist their growth.

However, antibacterial components are also present in the saliva including agglutinins, lysozyme, histatins, peroxidase, thicyanate, and lactoferrin.

Front 4

Question 4: state 2 functions of salivary agglutinins

Back 4

helps to clump bacteria together

block adhesion of bacteria

Front 5

Question 5: list 3 components of the salivary pellicle

Back 5

- Albumin
- Lysozyme
- Histatins
- Alpha amylase

Front 6

Question 6: give 6 examples of defense mechanisms in the oral mucosa and salivary glands

Back 6

surfaces are continuously flushed
Mucosal Epithelia (Salivary antibody)
Innate Defences - Mucosal barrier, defensins, calprotectins,adherent mucin, desquamation,
Adaptive Defences
- S-IgA is the primary immune agent produced by plasma cells,
- lymphocytes (B cells and T cells)

Inflammatory (part of innate)

Front 7

Question 7: identify on important hurdle to overcome in the development of a caries vaccine.

Back 7

There is lack of convincing evidence that the vaccines are effective
Vaccine trial is difficult due to fear of side effects (could damage the heart)
Incidence of dental caries is falling hence there is less interest in terms of economy

Front 8

Question 1: State why hepatitis A virus is an important consideration for dental health care professional considering the virus causes no oral pathologies.

Back 8

HAV causes no oral pathologies. However, the contagious manner of HAV is a consideration for oral health care professionals.

Front 9

Question 2: Describe 4 features common to viruses in the family Herpesviridae and give 2 examples of viruses in this family and their relative prevalence in the population.

Back 9

- large viruses (200 nm)
- large double stranded genomes consisting of around 200,000 bases.
- have an icosahedral nucleocapsid
- have a lipid envelope.

HSV-1 is a common virus and present in about 50% of the population.
HSV-2 is present in 5% of the population.

Front 10

Question 3: Explain the basis of recurrent oral disease due to Herpesviruses.

Back 10

remain dormant within the cells until immune system is lowered

active viruses are removed by immune system but those laying dormant are not removed

symptoms remerge as the immune system falls again

Front 11

Give 2 examples of Human herpesviruses that may cause cancer and the types of cancer the viruses cause.

Back 11

HHV-4 (Epstein-Barr Virsus - EBV) causes various cancers
In B-Cells (Burkitt’s lymphoma)
Nasopharyngeal cancer

HHV-8: Aetiological agents of Kaposi’s sarcoma. This is a tumour of the blood vessels in the skin (common in AIDS pt)

Front 12

Question 5: Define HPV and the most common oral clinical presentations caused by these viruses.

Back 12

HPV are members of the family Papovaviridae and are named because of the clinical conditions they cause: papillomas and warts

Most common clnical presentation of HPV oral disease: warts on the oral mucosa

Front 13

Compare and contrast 3 different forms of syphilis

Back 13

Front 14

Question 7: Name 2 non-syphilitic oral diseases that originate from systemic bacterial infections.

Back 14

Tuberculosis
· Leprosy

Front 15

Question 8: briefly describe acute suppurative parotitis including 2 bacterial pathogens that commonly cause these diseases and 2 predisposing factors.

Back 15

Suppurative means ‘pus forming’. Acute suppurative parotitis occurs mostly in adults with salivary gland abnormalities, or in dehydrated or post-operative individuals.

Very common pathogen: alpha haemolytic streptococci, S. aureus

Predisposing factors include:
-Drugs that reduce salivary flow – histamines
-Salivary abnormalities – calculus or mucous plug
-Sjogrens syndrom (progress degenerative disease affecting salivary glands)

Front 16

Question 1: Name the single most common fungal species isolated from lesions of the oral mucosa and 3 predisposing factors that increase susceptibility to this pathogen.

Back 16

Candida albicans

P Factors
Age: very old or very young
Co-existing infections: HIV
Physical conditions: dentures, smoking
Immune system: leukemia

Front 17

Question 2: comment on 5 fundamental features of Fungi.

Back 17

Fungi are in the domain Eukarya,

only 150 causes disease out of millions of types of species

Fungi are vegetative, do not synthesize chlorophyll

Share some structural and metabolic features of animal cells (nucleus, mitochondria, ribosome)

Non-motile,

Fungal replication can be sexual or asexual.

Rigid cell wall around the plasma membrane that contains sterol

Front 18

Question 3: describe 3 ways in which oral fungal pathogens are spread.

Back 18

Many oral fungal infections, including notable candidiasis, are communicably spread.

Portal of Exit- leaving this niche (ie mouth) and causing disease in other sites in the body such as the genitourinary tract

Portal of Entry (route of entry) - respiratory intake of fungal spores for Candida, and direct skin contact for other fungi

Front 19

Question 4: define 2 sources of aspergillum

Back 19

airborne

rotting vegetables, pepper, spices

Front 20

Question 5: indentify and briefly describe 4 non-candida oral fungal diseases.

Back 20

Aspergillosis:Saprophytic, Allergic, Acute invasive Aspergillosis

Cryptococcosis: reservoires are birds, rotten fruites&vegetables. Oral lesions present as ulceration or nodules on the tongue, palate, gingival tissue

Histoplasmosis: Reservoir is soil enriched with excreta from chickens and bats. Prevalent among HIV patients, and presents as ulcerated or nodular lesions, affecting the palate, tongue, buccal mucosa, gingiva, and lips.

Blastomycosis:symptoms similar to tuberculosis. Oral lesions are due to dissemination from pulmonary disease

Front 21

Question 7: compare angular stomatitis and median rhomboid glossitis.

Back 21

Median rhomboid glossitis

commonly presents as a diamond-shaped lesion on the dorsum of the tongue near the midline.

Angular Stomatitis: These lesions present in one or both angles of the mouth