1/9 Kingsley Caries Microbiology and Immunology Flashcards
Points of intervention for caries development
- fermentable carbohydrates
- biofilm formation
- acid formation
- demineralization (white spot lesions leading to caries)
Common sweeteners and preservatives
- sucrose
- fructose
Order of most cariogenic sweeteners to least
sucrose > fructose > other sweeteners
Bacterial enzymes convert carbohydrates using what enzymes?
- glucosyltransferase (GTF)
- fructosyltransferase (FTF)
- virulence factors
Initial colonizers mediate:
adhesion to tooth
Initial colonizers of tooth include:
S. sanguis, S. mitis
Initial colonizers alter the salivary pellicle to allow ____ to attach
S. mutans
Production of glucans and fructans produces ____ which allows for ____ adhesion, through ____ and ____
biofilm; sucrose-dependent; glucans binding protein (GBP) and virulence factors
In the production of biofilm, there is a change in _____ which traps ____
Diffusion properties; lactic acid
Sucrose-dependent adhesion can modify the:
Salivary pellicle
Acid formation occurs through ____ reactions via _____
Anaerobic; fermentation pathways
Example of acid formation through anaerobic reaction
S. mutans creates glucans and lactic acid
3 components of caries model
- diet (carbohydrates)
- microbiology (bacteria)
- biofilm (glucans, fermentation)
True or false: sugar substitutes have lower calories and cannot be fermented or metabolized
True
True or false: sugar substitutes do not affect cariogenic process
False: reduce it
Example of sugar substitute
Sugar alcohol - xylitol, sorbitol, mannitol
Sugar substitutes are considered ____
Anti-cariogenic
Sugars are modified via the addition of _____ to be converted into a sugar alcohol
OH group
Initial salivary pellicle binding includes ____ organisms such as:
gram positive (cocci, bacillus); S. sanguis, S. mitis, Actinomyces naelundii (viscosus)
Modified salivary proteins improve ____ for other microbes such as:
Adhesion; S. mutans, Lactobacillus
GBP binds:
glucans and fructans
Which bacteria use sucrose-dependent adhesion to adhere to biofilm?
- S. mutans
- Lactobacillus sp.
- S. sobrinus
- S. wiggsiae
All use GBP to bind
S. mutans classification (2)
- Gram positive cocci
- viridans strep group (alpha hemolytic)
S. mutans serotypes - Human pathogens
C, E, F
Percentage of S. mutans correlates with:
Sucrose intake
S. mutans virulence factors
- GTF enzyme
- GBP (adhesion)
- homolactic fermentation (acidogenic)
- acid tolerance (aciduric)
Examples of Lactobacillus sp.
- Lactobacillus fermentum
- Lactobacillus rhamnosus
- Lactobacillus gasseri
- Lactobacillus casei/paracasei
- Lactobacillus salivarius
- Lactobacillus plantarum
Streptococcus sobrinus is found in:
Severe, advanced caries lesions
Early caries is associated with what bacteria?
- S. mutans
- Lactobacillus
Advanced caries associated with what bacteria?
- S. mutans
- S. sobrinus
- S. wiggsiae
Scardovia wiggsiae has higher ____ and lower ____
Fluoride tolerance; enolase sensitivity
Fluoride inhibits _____ which prevents entry into ____
Enolase; glycolytic pathway
Fluoride forms ____ which makes enamel more resistant to acid
Fluorapatite
Fluorosis
Discoloration in surface pits and irregularities
Fluoride over exposure during tooth development can lead to:
Fluorosis
Topical medication used to treat and prevent dental caries
Silver diamine fluoride
Silver diammine fluoride is used for children with ____ and only on _____
SECC (severe early childhood caries); deciduous teeth
Silver diamine fluoride may not work on:
Scardovia wiggsiae
Lysozyme is produced by:
Both major and minor salivary glands
Lysozyme is known to function as:
Potent anti-bacterial agent in most mucus secretions
Lysozyme hydrolyzes:
beta 1,4 bond between NAG and NAM (peptidoglycan)
Hereditary disorder associated with gene for lysozyme
Hereditary non-neuropathic systemic amyloidosis
True or false: disorders associated with a lack of lysozyme are common
False - very rare
Lysozyme is so basic and fundamental to innate immunity
True or false: no relationship to oral health risk with hereditary non-neuropathic systemic amyloidosis
True - only two known familial cases in recorded medical history
Lactoferrin is produced and secreted in:
- saliva
- tears
- nasal secretions
- breast milk
Lactoferrin is known to function as a ____ in most mucus secretions that restricts the availability of _____ which are needed for bacterial growth
potent antibacterial agent; iron ions
Lactoferrin gene polymorphisms (SNPs) confers:
protective advantage against caries (against S. mitis, S. mutans)
confers differential oral risk
Proline-rich proteins are produced and secreted in _____ and comprise a significant portion of the _____
Saliva; salivary pellicle
Statherins help to maintain ____ and comprise a significant portion of the _____
enamel integrity; salivary pellicle
Statherin gene polymorphisms (SNPs) or variants may modulate:
Caries risk
Statherin SNP example
truncated statherin from a 24 bp deletion, missing first 8 N-terminal amino acids
Innate immunity and dental caries risk is associated with what proteins/components?
- lysozyme
- lactoferrin
- Proline-rich proteins
- statherins
- defensins
- mucins
_____ form pores in microbial membranes and are part of the fluid phase of saliva
Defensins
Defensins SNPs: ______ associated with high DMFT scores
HBD1 or DEFB1 rs11362
_____ are the major class of non-immunoglobin agglutinins
Mucins
Function of non-immunogobin agglutinins
Agglutinate or aggregate oral bacteria and inhibit adhesion or colonization on mucosal or tooth surfaces
MG2 gene polymorphism (SNP) examples
- MUC7 gene 6/6 had increased caries risk
- MUC7 gene 5/6 did not exhibit any increase in caries risk
Specific immunity and dental caries risk involves:
- IgA and IgM and blood groups
- primary immunodeficiency
- autoimmunity and hypersensitivity
B and T cells following activation become:
Memory cells
Immunologic memory allows for _____ immune response
More rapid and more robust
True or false: IgM has an extra CH domain
True (CH4)
What joins CH domains of IgM?
J chain
Which antibody is most efficient at agglutination and complement fixation
IgM
IgM structure
Pentamer
Serum IgA is a:
Monomer
Secretory IgA is a:
Dimer
Secretory IgA CH domains are linked by:
J-chain (plasma)
Secretory piece of secretory IgA made in:
Epithelial
Most produced antibody
Secretory IgA
Lowest DMFT score is found in what blood group
O (anti-A and anti-B antibodies)
Highest DMFT score is found in what blood group
AB (no antibodies)
_____ has a low (but not lowest) DMFT score
____ has a higher (but not highest) DMFT score
Blood group A; Blood group B
Most common immunodeficiency
Selective IgA deficiency
Selective IgA deficiency: most are asymptomatic due to:
IgM compensatory effect
Those with Selective IgA deficiency have an _____ in DMFT score
Increase
Sjogren’s syndrome: SSA autoantibodies affect?
Salivary and lachrymal (exocrine) glands
Primary manifestation of Sjogren’s syndrome
Dry mouth and dry eyes (xerostomia and keratoconjunctivitis sicca)
Sjogren’s syndrome treatments
Anti-histamines contraindicated, pilocarpine
Xerostomia ___ caries risk
Increases
Sjogren’s syndrome has a greater or lesser DMFT score than IgA deficiency?
Greater (4.1x)
What bacteria is associated with both early and advanced caries?
S. mutans
PRP gene polymorphisms (SNPs) or variants may modulate _____
Caries risk
Examples of PRP gene polymorphisms
- PRH1
- PRH2
PRH1 allelic variants is a ____ gene polymorphism that confers ______ from _____
PRP; increased caries risk; low to moderate
PRH2 allelic variants is a ____ gene polymorphism that confers ______ from _____
PRP; increased caries risk; low to high
_____ have increased caries risk regardless of sugar intake or hygiene
PRH2 allelic variants