Periodontal Microbiology Flashcards
What are the mucosal infections?
- Thrush- Angular cheilitis- Denture stomatitis
What are the periodontal infections?
- Gingivitis- Periodontitis
What are the influences on the oral microflora?
- Host factors- Diet- Saliva- Gingival crevicular fluid- Microbial interactions- Gaseous environment
What is meant by host factor influence on oral microflora?
- Systemic disease- Antibiotic use- Oral hygiene methods
What is included in diet influence on oral microflora?
- Chemical composition- Physical consistency- Frequency of intake
What is included in saliva influence on oral microflora?
- Flow rate- pH balance- Antimicrobial factors
What is included in gingival crevicular fluid influence on oral microflora?
- Antimicrobial components- Humoral immunity
What is included in microbial interactions influence on oral microflora?
- Competition- Co-operation
What is included in gaseous environment influence on oral microflora?
- Oxygen conc
What are the periodontal classifications?
- Gingivitis- Chronic perio- Aggressive perio- Necrotising periodontal disease- Peri-implantitis
What is included within active disease microbiologically and immunologically?
- Cytotoxins- Proteinases- LPS- H2S- Pathogenic bacteria- Non-protective immune responses- Disruption of tissue homestasis
What are host factors for development of periodontal disease?
- Smoking/tobacco use- Genetics- Pregnancy/puberty- Systemic disease- Nutrition
In a healthy tooth what bacteria is present within tooth pocket?
- Colonisation of normal oral flora- Healthy gums (gingiva)
In tooth with gingivitis what is present within pocket?
- Proportion of periodontopathogenic bacteria increases- Mild inflammation at edge of gum
In tooth with periodontitis what is present within pocket?
- High conc of periodontopathogenic bacteria- Severe inflammation and pocket formation- Degradation of soft and bone tissue
What are the development phases of bacteria?
- Naked surface with no bacteria- Conditioning film with host salivary glycoproteins- Linking film e.g. streptococcus- Coaggregation, re-conditioning film e.g. Actinomyces and Streptococcus- Accumulation, Shedding e.g. Actinomyces, Streptococcus and Fusobacterium
What type of bacteria is present in health, gingivitis and periodontitis?
Health = gram-positive aerobicGingivitis = on its way to gram-negative anaerobicPeriodontitis = Gram-negative anaerobic
How does the biofilm develop?
- Adhesion of bacteria- Colonisation of bacteria- Accumulation of different bacteria- Creates a complex community- Then dispersal of bacteria occurs
What bacteria is present in health?
- Oral streptococci, - Actinomyces - Fusobacterium
What bacteria is present in gingivitis?
- Actinomyces- Prevotella intermedia- Bacteroides- Fusobacterium nucleatum
What bacteria is present in periodontitis?
- Porphyromonas gingivalis - Prevotella intermedia
What is a commensal community compared to disease community?
Commensal has constraint and exclusion of pathogensDisease has overgrowth of pathogens
How is a multi-species biofilm formed?
- Colonisations occurs through adhesion molecules- Early colonisers of various streptococcal species bind to acquired pellicle- Actinomyces and Veillonella species associate closely with Streptococcal species- Form primary layer of bioflilm- Intermediate colonisers like F. nucleatum adhere to primary complex members- Pathogenic bacteria like P.gingivalis and A.actinomycetemcomitans bind to intermediate colonisers- Forms multi-species biofilm
What is Porphyromonas gingivalis?
- Oral pathogen- Gram-neg non-motile rod, strict anaerobe- Black pigmented from iron accumulation from hemin
