Unit 14 quiz Guha Flashcards
What is dental carries? How does it relate to bacteria?
Dental carries is the localized chemical dissolution of tooth surface by acid from metabolic actions of cariogenic bacteria in the biofilm or dental plaque.
What are the factors controlling carries? Keyes triad.
Three overlapping circles,
1) Host and teeth
2) Diet
3) Microflora
Only when all 3 overlap it results in Carries. so if only 2 overlap there shouldnt be any carries.
What are the 6 cariogenic bacterias mentioned in lecture?
1) Streptococcus Mutans
2) Streptococcus sobrinus
3) Streptococcus Snaguis
4) Streptococcus Salvarius
5) Lactobacillus
6) Actinomyces
What are the cariogenic factors of Streptococcus mutans? Why are they are more cariogenic? 5 mentioned in lecture.
1) It can adhere to cell surface utilizing adhesins and glucans while others only adhere via glucans.
2) Faster at forming lactic acid than other bacterias and formation can continue in absence of exogenous sugar supply.
3) Has higher acid tolerance than other bacterias (Except lactobacilli)
4) They can store polysaccharides intracellularly.
5) They introduce bacteriocins which actually work to eliminate competitors in oral plaque ecosystem .
What is the carries development mechanism?
1) Bacteria break down cariogenic food.
2) The release of acids.
3) PH drops in the mouth below 5.5 that will cause enamel to start breaking down from bacterial acids.
4) sugars lower PH level
5) Longer the teeth are exposed to low acid the more likely to develop caries.
What is cariogenic food?
Fermentable carbohydrates foods that can be broken down in your mouth.
examples: starchy or sugary food such as bread, candy, and crackers.
What type of carbohydrates can be broken down int he mouth?
1) Monosaccharides such as glucose, fructose, and galactose.
2) Disaccharides which are 2 monosacchrides (Suprise suprise). such as surcose, lactose ad maltose.
3) Oligosaccharides which is composed of 3-10 molecules of monosachrides such as starch and cellulose
Carcinogenicity and starch. Are cooked staple starchy food such as rice and potato high in cariogenicity? How high is the cariogenicity of uncooked starch? What about finely ground and heat treated starch, can it induce dental caries as much as sugars?
So what about mixing sucrose and starch vs just starch? which one is more cariogenic?
- Cooked staple starch such as rice and potatoes are low cariogenicity.
- Uncooked starch is low in caries development
- Finely ground and heat treated starch is cariogenic but lower than that of normal sugars.
-A mix of sucrose and starch and just sucrose is equally bad if they’re presented in the same amount.
Which sugar is the worst and why?
Sucrose because all sugars can be fermented but sucrose not only act as a substrate ut also can be a substrate for IPS production for biofilm.
What are some factors of the cariogenicity of food? 8 factors in the slides.
- Consistency of food
- chewing efficiency of the host
- Temperature
- clearance of food from the mouth
- Hydrolysis of monosaccharides
- Location, composition, and consistency of biofilm.
- buffering capacity
- Food consumption pattern
What are the 3 ways fluoride prevents caries?
1) it binds to enamel crystal surface and transforms hydroxyapatite into more stable fluorapatite.
2) Fluoride would remineralize after demineralization
3) Fluoride inhibits the bacterial metabolism of sugar and reduces caries.
What is sorbitol?
Sorbitol is non-cariogenic sugar alcohol that’s used as a sweetener.
- Cannot be fermented by dominant bacteria
- Fermentation is much slower than sucrose and glucose
- Most of the products of sorbitol fermentation are formic acid and ethanol and very little lactic acid.
What is xylitol?
-Xylitol is another sugar alcohol that is none cariogenic and is not fermented by oral microflora.
- IT ACTUALLY kills bacteria by entering bacteria and degrading them
- It reduces the S. Mutans count in plaque and prevents S. Mutans from binding to the tooth surface.
-The anti cariogenic abilities depends on the frequency of chewing.
What are some protective foods?
- Cow milk is noncariogenic although it has lactose.
- Calcium in milk also help remineralize
- Cheese increases PH and increased plaque calcium concentration
- Casein is another anti cariogenic component of dairy products.
- Sugar-free gums nowadays contain casein phosphates.
