Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
74 Cards in this Set
- Front
- Back
|
What is the primary etiologic agent initiation dental caries?
|
Streptococcus mutans
|
|
|
The bacteria that produce dental caries must have the ability to produce what?
|
Insoluble Glucans
|
|
|
What are two types of glucans that are both polymers of glucose?
|
Dextrans and Mutans
|
|
|
What types of bacteria produce dextrans and mutans?
|
Streptococcus Sanguis
mutans salivarius lactobacillus |
|
|
What are polymers of fructose?
|
Levans
|
|
|
What bacteria produce levans?
|
Streptococcus salivarius
mutans sanguis lactobacillus casei acidophilus |
|
|
what is a gram-negative coccobacillary rod?
|
Actinobacillus
|
|
|
What bacteria is found in the normal flora in the upper respiratory tract?
|
Actinobacillus actinomycetemcomitans (AA)
|
|
|
What damage does Actinobacillus actinomycetemcomitans (AA) do?
|
Opportunistic pathogen
Causes endocarditison damaged heart valves and sepsis. |
|
|
Where is AA most commonly implicated?
|
With etiology of localized aggressive juvenile periodontitis
periodontitis in juvenile diabetes |
|
|
What bacteria causes root-surface caries?
|
Actinomyces viscous and naeslundii
|
|
|
What are synthesized from dieatary sucrose by cariogenic and plaque bacteria primarily as extracellular polysaccharides?
|
Dextrans, mutans, levans
|
|
|
What has been shown to be the most effective antimicrobial agent for reducing plaque and gingivitis long-term?
|
Chlorohexidine
|
|
|
Why is chlorohexidine considered to be so effective?
|
Greatest residual concen. in mouth after use
Rapidly absorbed onto teeth and pellicle Slowly released |
|
|
What is chlorohexidine approved as by the ADA?
|
Antimicrobial and Antigingivitis agent
|
|
|
What are some examples of chlorohexidine?
|
Peridex and Periogaurd
|
|
|
What is the most common side effect of chlorohexidine?
|
Temp. superficial staining of oral structures
|
|
|
What are three other topical antimicrobials besides chlorohexidine?
|
Stannous fluoride
Phenolic compounds Quaternary ammonium compounds |
|
|
What is the antimicrobial action in stannous fluride related to?
|
Stannous tin ion instead of fluoride ion
(Gel Form) |
|
|
What does the ADA accept stannous fluoride for?
|
Anticaries
NOT - Antiplaque or antigingivitis |
|
|
What are phenolic compounds approved for by the ADA?
|
Antimicrobial / antigingivitis
|
|
|
What is an example of a phenolic compound ?
|
Listerine
|
|
|
What compound seems to be not as effective as others in reducing plaque or gingivitis, but seems very effective at eliminating bad breath (halitosis)?
|
Quaternary ammonium compounds
(scope / cepacol) |
|
|
Which specific bacteria species have been implicated in the dental caries process?
|
Streptococcus
S. Mutans S. Sanguis S. Salivarius |
|
|
What is the most frequently isolated streptococcus in the oral cavity?
|
S. Sanguis
|
|
|
What do Steptococcus bacteria do in the mouth?
|
Produce detran sucrose that catalyzes formation of extracellular glucans from dietary sucrose.
|
|
|
What is another name for dextran sucrose?
|
glucosyltransferase
|
|
|
What does glucan production contribute to?
|
Formation of dental plaque
|
|
|
What does dental plaque hold that is produced by streptococci against the tooth?
|
Lactic acid
|
|
|
What does lactic acid dissolve on the tooth?
|
Hydroxyapatite crystals
|
|
|
What is the major cariogenic property of S. mutans?
|
Production of enzyme
glucosyltransferase |
|
|
What are the essential properties that are necessary for caries formation?
|
Adhere to tooth
Lactic acid production Produce polymeric substance that causes acid to remain in contact with the tooth |
|
|
What are the prerequisites for development of caries?
|
Cariogenic bacteria
Susceptible host Supply of substrate for lactic acid production |
|
|
What is the principal site for the growth of gram negative anaerobes like spirochetes, and fusobacteria?
|
Gingival sulcus
|
|
|
Why is the gingival sulcus susceptible to these bacteria?
|
1. Increase crevicular (gingival) fluid
2. Desquamation of epithelial cells 3. Bacterial acid products |
|
|
What kinds of bacteria does a normal healthy mouth consist of?
|
Obligate / Facultative anaerobes
Acidogenic bacteria |
|
|
True False:
The influenceing bacteria for periodontal disease is the same bacteria that is normally present in a healthy mouth. |
True
these bacteria become opportunistic |
|
|
What bacteria produces hydrogen peroxide?
|
S. Sanguis
S. Mitis |
|
|
What bacteria is aciduric and produces lactic acid?
|
S. Mutans
Lactobacillus casei |
|
|
What bacteria is found consistently in saliva and on oral soft tissue?
|
S. Salivarius
|
|
|
What are the most numerous group of bacteria in the oral cavity, are gram positive cocci and are facultative anaerobes?
|
Streptococci
|
|
|
What is the percentage of plaque components?
|
Water (80%)
Solids (20%) - 95% of this is bac. |
|
|
What are the stages of plaque formation?
|
1. Formation of the pellicle
2. Bacterial colonization 3. Maturation Stage |
|
|
Surface coating of salivary origin, which is primarily protein in nature, with some carbohydrate complexes. Essentially structureless and bacteria-free. Forms on clean teeth within minutes.
|
Acquired pellicle
|
|
|
Why does the pellicle form within minutes on a clean tooth surface?
|
Due to its salivary origin
|
|
|
What surfaces will the acquired pellicle form on?
|
Tooth
Crowns Dentures Porcelain teeth |
|
|
What is the order of bacteria deposition on the tooth during the bacterial colonization phase of plaque?
|
Orderly
1. Streptococci (gram positive) Large amounts 2. Rod shaped microorganisms (Bacteroides and fusobacterium) Attach and colonize 3. Mature plaque cause morph shift to filamentous bac. (actinomyces) |
|
|
Saliva contnues to provide agglutinating substances and other proteins to the intercellular matrix, and bacterial intercellular adhesion results. The crystalline structure will increase and eventually calcify. (calculus)
|
Maturation Stage of pellicle formation
|
|
|
What is young plaque dominated by?
|
gram-positive cocci
|
|
|
What is usually one of the first colonizers of plaque?
|
Streptococcus sanguis
|
|
|
What is the percentage of gram positive cocci in young plaque?
|
40-50% streptococcus
|
|
|
What is the percentage of gram positive rods in young plaque?
|
10-40% lactobacillus
|
|
|
What is the percentage of gram negative rods in young plaque?
|
10-15% Fusobacterium
|
|
|
What is the percentage of filaments in young plaque?
|
4% or less
Actinomyces and Veillonella |
|
|
What changes occurs when plaque ages?
|
50% gram + and 30% gram -
# cocci decrease / # filaments increase Aerobic bac. decrease / Anaerobic bac. increase |
|
|
How long does it take for calculus to mineralize both sub and supra gingivally?
|
12 days
|
|
|
What are the inorganic components of calculus?
|
70-90%
Calcium and phosphate Small amount magnesium / carbonate (from saliva) Hydroxyapatite / Fluoride |
|
|
What are the organic components of calculus?
|
Microorganisms (same as plaque)
Desquamated epithelial cells leukocytes mucin |
|
|
How is calculus mineralized?
|
Bathing in saliva giving it calcium and phosphorus
|
|
|
Why is subcalculus dark?
|
Due to pigments from blood break down
|
|
|
Which has more anaerobes?
Supra- or sub- gingival plaque? |
Subgingival
|
|
|
What alters bacterial composition?
|
Saliva and diet
|
|
|
What are the main characteristics of supragingival plaque?
|
- Attached or tooth associated
- Gram + anaerobic cocci - As ages vibrios, spirochetes and gram neg. bact. predominate |
|
|
What are the bact. that are associated with supragingival plaque?
|
S. Sanguis, actinomyces viscosus, naeslundii
|
|
|
What are the main characteristics of subgingival plaque?
|
- Lossely attached (epi. associated)
- gram neg. anaerobic rods |
|
|
What are the bact. associated with subgingival calculus?
|
Actinomyces
Fusobacterium nucleatum Treponema (spirochetes Veillonella |
|
|
The progression from a healthy gingival sulcus to gingivitis is associated with a shift towards what?
|
gram-negative bacteria
|
|
|
What bacteria is commonly implicated in the etiology of acute necrotizing ulcerative gingivitis?
|
Prevotella intermedia
|
|
|
Condition which presents rather pathognomonic (characteristic of a single disease) within the oral gingiva.
|
ANUG
|
|
|
What are the clinical signs of ANUG?
|
(Important)
Interproximal necrosis History of soreness and bleeding gums (Less Important) fetor oris (offensive odor) low-grade fever lymphadenopathy malaise |
|
|
What is the dominant WBC in the inflammatory infiltrate of ANUG?
|
neutrophil
|
|
|
When does ANUG most often occur?
|
Adults between 18-30
|
|
|
What are factors which offer a predisposition of ANUG?
|
Gingivitis
Tobacco smoking gross neglect (bad hygiene) fatigue stress |
|
|
What are all of the bacteria associated with ANUG?
|
Intermediate sized spirochetes
Prevotella intermedia Fusobacterium species Selenomonas species |
