Microbes in Oral Health and Disease Flashcards
What does ‘commensalism’ mean?
An association between 2 organisms in which one benefits and the other neither receives any benefit nor harm
Which category do most bacteria in our oral cavity fall under?
Commensals
What does ‘parasitism’ mean?
A symbiotic relationship in which one organism benefits, causing the other organism harm in doing so
What does ‘mutualism’ mean?
A symbiotic relationship in which both organisms involved receive mutual benefit
Which factors lead to a healthy host?
- Immune system
- Vaccines
- Antimicrobial agents
Which factors lead to disease in the host?
- Immuno-suppression
- Virulence factors
- Resistance
What are the contributors to oral health?
- Integrity of oral mucosa
- Lymphoid tissue
- Saliva
- Gingival crevicular fluid (GCF)
- Humoral and cellular immunity
What is flagella used for?
Motility
What are pili used for?
Adhesion
What is the predominant immunoglobulin present in saliva and what does it do?
- IgA
- Prevents microbial adherence to host surfaces
What is lysozyme and what does it do?
A bactericidal enzyme present in saliva that breaks down components in bacterial cell wall
How many microorganisms are present per ml of saliva?
10^8
Name 3 species of bacteria that are involved in dental caries
- Streptococcus mutans
- Lactobacillus species
- Actinomyces species
Which 4 factors must be present for caries to develop?
- Susceptible tooth surface
- Sugar
- Time
- Plaque bacteria
What does periodontal disease affect?
- Supporting structures of the teeth: gingiva, periodontal ligament, alveolar bone
- Chronic long lasting inflammation
What is marginal gingivitis?
Inflammation around gumline
What is hyperplastic gingivitis?
- Gingivitis that persists for a long time and is characterised by the proliferation of fibrous connective tissue causing enlarged firm gums
- Also called proliferative gingivitis
What is hyperplastic gingivitis also known as?
Proliferative gingivitis
What are the features of advanced periodontal disease?
Detatchment of the periodontal ligament alveolar bone loss and eventual tooth loss
What does ‘purulent’ mean?
Consisting of, containing or discharging pus
What are the features of purulent infections in the oral cavity?
- Pus forming
- Formation of an abscess
Intra/extra-oral swelling
How can pseudomembranous candidiasis be treated?
- Scraping it off
- Treated with anti fungal drugs
What is candidal leukoplakia?
- Variant of oral candidiasis
- White patches that cannot be scraped off
- Organism has grown into the membrane
- Associated with premalignancy
Which bacterial/fungal species cause angular cheilitits?
Candida species or staphylococcus aureus
