question

The etiology (study of causation, or origination) of dental caries involves ___________ (4 things)

answer

1. A susceptible tooth
2. Specific Plaque microflora
3. A specific diet (frequent consumption of sucrose or other fermentable carbohydrates)
4. Combination of these 3 elements for a sufficient period of time.

question

True or False
Caries takes place right after it is exposed to a susceptible tooth.

answer

False
Only takes place when all factors are present! If one factor is absent, caries will not occur!

suceptible tooth
specific plaque microflora (cariogenic bacteria),
A specific diet (sucrose or other fermentable carbohydrates)
and the combination of these for the right amount of time.

question

True or False
Caries can be prevented by removing or changing one of the factors that are involved.

answer

True

question

What conclusions were found from the Vipeholm Dental Caries Study (1946-1951)

answer

Retentive sugar was more cariogenic than non-retentive.
Sugar consumption between meals is more cariogenic than at mealtime.
The FREQUENCY of sugar intake/day is more important in caries initiation than the amount of sugar consumed/day.
Sugar restriction can inhibit new caries formation in individuals who exibited active caries.

question

study that found the "resting pH" (pH when there is no food around like when you first wake up in the morning) of plaque, which is around 7. The study uses a pH microelectrode that is introduced to plaque in vivo to examine pH variations of plaque when exposed to various substrates (subjects usually rinse with a glucose solution). The pH of plaques after diet exposure is plotted over time.

answer

Stephan Curve Studies (1944)

question

a family of streptococcal species which induced extensive caries in experimental animals in the presence of sucrose.

answer

Mutans streptococci (MS)

question

the main 2 species of Mutans Streptococci (MS) in humans

answer

1. Strep mutans
2. Strep sobrinus

question

True or False

Mutans streptococci (MS) are responsible for caries progression in the tooth and lactobacilli are responsible for caries initiation.

answer

False

MS = Responsible for caries initiation

Lactobacilli = causes caries progression in the tooth

question

The key environmental factors leading to a cariogenic microflora are: ______?

answer

1. A slightly acidic plaque environment pH (about 6.0, continuously).
2. Frequent exposure to dietary sugars (not other sugars)

question

When sucrose is consumed frequently over an extended period, ________?, will be formed by plaque bacteria, causing an increased plaque thickness which will inhibit saliva penetration and buffering. Also causes MS to proliferate (Increase rapidly in numbers).

answer

Extracellular
Polysaccharide
(ECP)

question

True or False

Mutans streptococci (MS) are not indigenous and strongly acidogenic (acid-forming)

answer

False
MS is strongly acidogenic
AND
it also IS indigenous

question

the acidic by-products (mostly lactic acid) of sugar fermentation by MS and the inhibition of salivary buffering result in sufficient mineral dissolution to create a ___________?

answer

Cavitation

question

When cavitation occurs, the environmental pH of the cavity will get even lower/more acidic and ___________ will proliferate in and dominate the ecosystem, and continue progression of the lesion into the dentin and to the pulp.

answer

Lactobacilli (which are most aciduric - acid loving <3)

question

True or false
MS colonizes only hard tissue or surfaces (tooth or appliance)

answer

True

question

An early colonizer of the tooth that occupies the deep regions of plaque adjecent to teeth.

answer

Mutans Streptococci
(MS)

question

________causes an expansion of MS

answer

Dietary sucrose

question

The principle origin of MS has been determined by genetic techniques to be:

answer

FROM MOM!
transmission to the infant occurs between 0-31 months

question

The preferred habitat of MS is _____?

answer

Dental Pits and Fissures (where they are protected from salivary buffers and the pH is slightly acidic)

*Other supra-gingival plaque retention sites (orthodontic brackets or partial dental clasps) may also serve as habitats.

question

MS do NOT thrive _____________? Where?

answer

Sub-gingival ecosystems
(pH is TOO ALKALINE)
(best grow in pH of about 6.0)

question

_________are more aciduric (tolerate a low pH; <3 Acid) than MS, but less acidogenic and will dominate cavitated and dentinal carious lesions.

answer

Lactobacilli (LB)

question

________ are indigenous, facultative Gram positive + rods that produce lactic acid from sugar. They can colonize on soft tissues and hard tissue and can acheive high levels in mouths of people who eat high sugar diets, DUE TO an acidic environment.

answer

Lactobacilli (LB)

question

True or False

Lactobacilli initiates caries and MS is secondary.

answer

False

MS initiates caries, LB is secondary.
(LB will continue the lesion into dentin but can NOT independantly initiate the disease - Needs MS)

question

cell-bound enzymes on the surface of MS which bind sucrose

answer

Glucosyl-transferases (GT)

question

A disaccharide of glucose + fructose

answer

Sucrose

question

the particular glucan that is made by MS and that is responsible for succession (increase in numbers) of MS in plaque.

answer

Mutan

question

the protein adhesins that are attached to the cell wall of all MS. These bind to any type of glucan and are not enzymatic.

answer

Glucan
Binding
Sites
(GBS)

question

MS are more pathogenic than other streptococci because they are more ___________??

answer

Acidogenic (species that produce acid)

question

These are the most acidogenic species in the mouth and this property is responsible for their ability to form a carious lesion in enamel.

answer

Mutans streptococci (MS)

question

This is the main acid formed by MS

answer

Lactic Acid

question

List characteristics of Chronic Gingivitis.

answer

Tissue is inflamed
Color changes from pink to dark red
Tissue becomes transparent/hyperemic (blood capillaries appear)
Loss of stippling
Gingiva bleeds when touched (probe, brushing...)
Pseudo-pockets form (deepening of gingival crevice) but the gingival attachment apparatus is not disrupted so it is not a true pocket. (Fibers still attached at CEJ)
Usually not painful

question

this flows from the tissue through the sulcus into the oral cavity, removing bacteria and toxic substances. Present in health AND in disease

answer

Gingival
Crevice
Fluid
(GCF)

question

Characteristics of the microbial ecology when the gingiva is inflammed due to chronic gingivitis.

answer

Oxygen decreases
Gram Negative anaerobic species increase (since o2 is down)
Motile bacteria increases (spirochetes and vibriolike organisms) because they can swim to nutrients.
GCF increases
(so there is an overall shift to predominantly Gram negative, anaerobic and motile species which are detrimental to tissue integrity)

question

a painful gingivitis that affects mainly young people and is associated with psychological stress.

answer

Necrotizing
Ulcerative
Gingivitis
(NUG)

question

Purulent (associated with pus) whitish accumulations that cover affected lesions/tissue during NUG. When they are removed, they reveal severe ulceration where interdental papilla used to be (becuase they are gone now...because of disease)

answer

Pseudo-membrane

question

List characteristics of Necrotizing Ulcerative Gingivitis (NUG)

answer

Extremely painful to eat (esp salty and spicy), brush, and dentist manipulations.
Interdental papilla totally wiped out to the connective tissue.
Strong odor - foul, resembles necrosis and putrefaction.
Self-Limiting clears up on its own in about 2 weeks

question

specimens in NUG are typically all __________?

answer

Spirochetes

question

spirochetes are members of what genus?

answer

Treponema genus

question

Pregnancy gingivitis usually occurs during which trimester?

answer

the 2nd Trimester

question

Name the gingival pathogen of Pregnancy Gingivitis

answer

Prevotella intermedia (Pi)
a gram negative anaerobic rod

question

an increase in ___________ in GCF during pregnancy gingivitis is most likely acting as nutrients which stimulate the growth of the pathogen Prevotella intermedia (Pi)

answer

Increased hormones
(progesterone and estradiol)

question

type of gingivitis that is analogous to pregnancy gingivitis becuase it involves a spurt of hormones that act as nutrients for Prevotella intermedia.

answer

Puberty Gingivitis

question

Characteristics of puberty gingivitis

answer

Highly inflammed marginal gingiva
Sometimes painful
doesn't always correlate with dental plaque levels.

question

Characteristics of Chronic Periodontitis

answer

Oral malodor/bad breath
Calculus
Stains
Materia alba
Pocket formation/loss of attachment
Bone loss/resorption

question

this occurs in chronic periodontitis when the attachment apparatus (connective tissue fibers attached to the CEJ) become disrupted and reattach apically on the root surface.

answer

;
Periodontal pockets/
pocket formation

question

3 Pathogens of Chronic Periodontitis

answer

Porphyromonas gingivalis (Pg) (most pathogenic of the three/the worst one)
Treponema denticola
Tannerella forsythia

question

Predisposing factors/environmental factors that increase the risk/severity of Chronic Periodontitis

answer

Tobacco smoking
Physiological stress
Diabetes
High lipid diets
Altered immunity
Compromised health
Medications

question

calcification within plaque which is firmly attached to the tooth and is often found in periodontal pockets.; Some beleive it exacerbates periodontitis because its rough surface constantly irritates gingival tissue, also it increases the surface area which would house more bacteria.

answer

;
Calculus

question

Another term used to describe Aggressive Periodontitis (AgP)

answer

;
;
Early Onset Periodontal Diseases

question

this is characterized by very rapid pocket formation, very rapid bone loss with low levels of plaque and inflammation.; It is also genetic and occurs in younger individuals (Younger than 35 years)

answer

;
Aggressive Periodontics (AgP)/
Early Onset Periodontal Disease

question

the pathogen present in Aggressive Periodontitis (AgP)

answer

;
Aggregatibacter
actinomycetemcomitans (Aa)

question

gingivitis with a "band-like" bright red marginal gingivitis on buccal surfaces along with diffuse redness extending onto the attached alveoloar mucosa

answer

;
HIV related gingivitis and periodontitis

question

this can be either infection from a periodontal pocket;through a lateral canal or apical foramen into the pulp, or infection from a periapical abscess of an adjacent tooth through the apical foramen in the pulp.

answer

;
Retrograde
Periodontitis

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