CMS/Microbiology Flashcards
What are the stages in formation of a clot?
Vasoconstriction
Platelet plug formation
Fibrin clot formation (coagulation)
How does aspirin/warfarin/heparin affect clot formation?
aspirin- Reduces platelet aggregation
Warfarin- inhibits vit k dependent clotting factors 2, 7, 9, 10
Heparin- inactivates thrombin preventing fibrin formation (and clotting factors 5, 8 and platelets)
Why are aspirin and clopidogrel used together?
As they can be combined and have synergistic/additive effect
What pattern does Von Willebrands disease follow?
T1/2- autosomal dominant
T3- autosomal recessive
What causes effect of VWD on bleeding?
Deficiency of VWF and reduction of Factor 8
What is a biofilm?
Complex aggravation of microorganisms encased in highly hydrated matrix of exopolysaccharide excreted by microorganisms
What are the stages in biofilm development?
Adhesion
Colonisation
Accumulation
Complex community
Dispersal
What are the methods of identifying organisms?
Aspirate
Swab
Rinse
Biopsy
What are the virulence factors of P.Gingivalis?
Fimbriae- adhesion/invasion
LPS
Capsular polysaccharides
Proteases- collagenase, phospholipase, fibrinolysin,
gingpains
Tissue toxic metabolic products- ammonia, fatty acids
What are the virulence factors of Candida albicans?
Germ tube formation
Adhesins
Metabolic acids
Extracellular enzymes
Switching mechanism
What are the virulence factors of S.Mutans?
EPS/sucrose metabolism
Attachment mechanisms- gtf, ftf, glucan binding
Adhesins- SpaP
Acid tolerance- F1-F0 ATPase
What is difference between solids and liquids with regards to oral seal?
Posterior oral seal is required for ingestion of liquids
(No stage 2 transport)
-> During processing of solid foods the mouth is continuous with oro-pharynx
What is ingestion?
Movement of food from external environment into mouth
What is Stage 1 transport?
Food is gathered in tongue tip
-> tongue retracts pulling material back to posterior teeth
-> hyoid bone and narrowing of oesophagus occurs
What is mechanical processing?
Food is mixed with saliva to allow swallowing
Food is masticated by molars and premolars
Bolus is squashed against hard palate and tongue
What is stage 2 transport?
Bolus moves anterior posteriorly by squeeze-back
-> Solid foods move through fauces to pharyngeal surfaces of tongue
What is swallowing?
Involuntary movements push bolus through pharynx to oesophagus
UOS opens then epiglottis closes to prevent backflow
Peristalsis occurs to move bolus toward stomach
What are the stages in tooth development?
- Intiation- dental lamina
- Morphogenesis- bud/cap
- Cytodifferentiaton- bell
- Matrix secretion
- Root formation
What forms the root? How may this affect the dentition in later life?
HERS- can persist as debris of Malssez (can be source of cyst formation)
What are the different parts in the late bell stage?
Internal enamel epithelium
External enamel epithelium
Stellate reticulum
Stratum intermedium
