Etiology Flashcards
Can you cure periodontal disease?
No- you can treat it and reduce chance of progression though
Periodontal pathogenesis involves:
- environmental factors
- host factors
- microbial factors
Regarding periodontal pathogenesis smoking would be considered:
an environmental factor
Regarding periodontal pathogenesis, immune system/immune factors would be considered:
host factors
Regarding periodontal pathogenesis, plaque/biofilm would be considered:
microbial factors
When overgrowth of gram positive bacteria in susceptible individuals leads to gingival inflammation this is considered:
gingivitis
Gingivitis is a reaction limited to:
soft tissue area
The gingival inflammation in gingivitis alters:
subgingival microenvironment
What occurs in patients with gingivitis, when the gingival inflammation alters the subgingival microenvironment?
Overgrowth of “periodontal pathogens” in biofilm
When plaque causes a host immune inflammation reactions together with genetic predisposition and environmental influences are able to “contain” infection:
gingivitis
When plaque causes host immune and inflammatory reactions together with genetic predisposition and environmental influences are unable to “contain” infection:
Periodontitis
If gingivitis progresses to causing attachment loss or bone loss it is considered:
Periodontitis
If you are unable to see if there is dental plaque or not, what should you do?
Have patient use disclosing agent
The structurally and functionally organized, species-rich microbial biofilms that form on teeth:
dental plaque
Dental plaque is the main etiologic agent for:
- Periodontal disease
- Dental caries
-White cheesecake accumulation
-A soft accumulation of salivary proteins, bacteria, desquamated epithelial cells, and food debris
-No organized structure
-Easily displaced with a water spray
Materia Alba
What components comprise materia alba?
Accumulation of:
- salivary proteins
- bacteria
- desquamated epithelial cells
- food debris
Describe the structural makeup of materia alba:
NOT organized
Describe the removal of materia alba:
easily displaced with a water spray
-Resilient clear to yellow-grayish substance
-Primarily composed of bacteria in a matrix of salivary glycoproteins and bacterial products
-Considered to be a biofilm
-Impossible to remove by rinsing or spraying
Dental plaque
What components comprise dental plaque?
Bacteria in a matrix of salivary glycoproteins and bacterial products
Describe the structural makeup of dental plaque:
a biofilm
Describe the removal of dental plaque:
Impossible to remove by rinsing or spraying- requires mechanical removal
- mineralized dental plaque forms the hard deposit
- generally covered by a layer of unmineralized dental plaque
Calculus
Describe the structural makeup of calculus:
mineralized
Composition of dental plaque:
- water
- microorganisms
- intracellular matrix
What percentage of dental plaque is comprised of water?
70%
What makes up the “dry weight” of dental plaque?
Microorganisms & intracellular matrix
What makes up the ORGANIC component of intracellular matrix?
- polysaccharides
- proteins
- glycoproteins
- lipids
What makes up the INORGANIC components of intracellular matrix?
- calcium
- phoshphorus
(main components) - other minerals
- sodium
- potassium
- fluoride
What are the main two components that make up the inorganic portion of dental plaque?
calcium & phosphate
______ grams of plaque contains approximately 10^11 bacteria (and the human body has approximately 10^12 bacteria)
1 gram
More than _____ distinct microbial species can be identified in dental plaque with highly sensitive molecular techniques
500
What is dental plaque?
a) it is non organized structure with soft accumulation of salivary proteins, bacteria, desquamated epithelial cells, and food debris
b) it is the structurally and functionally organized, species-rich microbial biofilm that form on teeth
c) it is he hard deposit on the teeth surface which can be formed by the mineralization of the matrix of salivary glycoproteins and bacterial products
d) it is the ornamental tablet in commemoration of the contribution of dentistry
b
Sites of plaque accumulation include: (4)
- gingival thirds
-cracks, pits and fissures
-under overhanging restorations
-around maligned teeth
Why does plaque often accumulate on:
- gingival thirds
-cracks, pits and fissures
-under overhanging restorations
-around maligned teeth
Because these areas are harder to keep clean with brushing and flossing
Dental plaque classification is based on:
position on the tooth surface (toward the gingival margin)
Name the three classifications of dental plaque:
- supragingival plaque
- marginal plaque
- subgingival plaque
Describe subgingival plaque: (3)
- tooth attached plaque
- unattached plaque
- epithelial associated plaque
How may unattached plaque be removed?
by brushing
What type of bacteria makeup suprgingival plaque?
Gram + cocci and short rods
What is the oxygen requirement for supragingival plaque (bacteria comprising = gram + cocci and short rods)
aerobic environment
Describe the diversity of the bacteria comprising supragingival plaque:
slight diversity
What type of bacteria comprise subgingival plaque?
gram - rods & spirochetes
What is the oxygen requirement for subgingival plaque (bacteria comprising = gram - rods & spirochetes):
anaerobic environment
Describe the diversity of the bacteria comprising subgingival plaque:
greater diversity
Type of plaque associated with calculus formation & root caries:
supragingival plaque
Type of plaque that is in direct contact with gingival margin and associated with the initiation & development of gingivitis:
marginal plaque
Type of plaque associated with tissue destruction:
Subgingival plaque
(made of spirochetes that can swim from subgingival space into the tissue)
Steps involved in the formation of dental plaque: (3)
Step 1: formation of the pellicle
Step 2: initial colonization of bacteria
Step 3: secondary colonization and plaque maturation
What type of attachment is seen with formation of the pellicle (step 1) in dental plaque formation?
Reversible attachment
What type of attachment is seen with initial colonization of bacteria (step 2) in dental plaque formation?
Irreversible, specific, short range
How doe the secondary colonizers attach to the primary colonizers in dental plaque formation?
Co-adhesion
(initial colonizers used adhesion-receptor attachments)
List some of the processes that occur during the secondary colonization & plaque maturation (Step 3) of dental plaque formation:
- metabolic interactions
- environment modification
- gradient formation
- matrix synthesis
- cell-cell signaling
- bacterial growth
List the 6 steps of formation of dental plaque (further broken down steps 1-3):
- pellicle formation
2a. passive transport
2b. reversible attachment - adhesion-receptor (primary colonizers)
- co-adhesion (secondary colonizers)
- biofilm maturation
- detachment
Adsorption of a conditioning film:
acquired pellicle
An organic material layer coated on all surfaces in the oral cavity, including hard and soft tissues:
acquired pellicle
The acquired pellicle is a ____ layer coated on ______ surfaces in the oral cavity, including ______ tissues
organic; all; hard & soft
Components of the acquired pellicle are derived from:
saliva & crevicular fluid
What type of bacteria are involved with the formation of the acquired pellicle?
gram + facultative microorganisms
What is considered the INITIAL stage of development of the plaque?
formation of acquired pellicle
During formation of the pellicle, there is reversible adhesion between the _____ and the _____.
microbial cell surface (adhesins); conditioning film (receptors)
During formation of the pellicle, there is ____ adhesion between microbial cell surface (adhesions) and the conditioning film (receptors)
reversible
The reversible adhesion between the microbial cell surface (adhesins) and the conditioning film (receptors) alters the charge and free energy of the surface which:
increases efficiency of the bacterial adhesion
During initial colonization, the primary colonizers and secondary colonizers attach via:
co-adhesion
During the initial colonization after co-adhesion of the primary & secondary colonizers, there is an alteration in the:
oxygen gradient
Describe the alterations in the oxygen gradient seen during the initial colonization after co-adhesion of the primary & secondary colonizers:
Anaerobic conditions emerge in the deeper layers of deposits
List the bacterial species that are considered PRIMARY colonizers in the formation of dental plaque:
- Streptococcus spp.
- Hemophilus spp.
- Neisseria spp.
- Actinomyces spp.
- Veillonella spp.
List the bacterial species that are considered SECONDARY colonizers in the formation of dental plaque:
- Prevotella intermedia
- Capnocytophaga spp.
- Fusobacterium nucleatum
- Porphyromonas gingivalis
What is the term for secondary colonizers adhering to the bacteria that are already in the plaque mass during the formation of dental plaque?
Coaggregation
T/F: Coaggregation with the secondary colonizers adhering to the bacteria that are already in the plaque mass can be seen by the naked eye
True
Following colonization this process occurs through further colonization and growth of additional species during the formation of dental plaque:
Maturation
During maturation in the formation of dental plaque, bacteria use quorum sensing (cell-cell signaling) to:
- modify the environment
- metabolic interactions
Regarding the structure of the dental plaque:
- Open _____ running through plaque mass
- Distance ____ produced by matrix (steep chemical gradients)
- Quorum sensing results in _____
- fluid-filled channels
- microenvironment
- bacterial resistance
In periodontal microbiology what results in “corn-cob formation”:
Coccal-shaped cells attaching to tip of gram negative filamentous organisms
in periodontal microbiology “corn-cob formation” is an example:
Interbacterial adherence or congregation
List the microbiologic specificity hypothesis for the time period given:
a) 1900s
b) 1960s
c) 1990s
a) Nonspecific plaque hypothesis
b) Specific plaque hypothesis
c) Ecologic plaque hypothesis
Hypothesis that states “Direct relationship between the total amount of plaque and the amplitude of the pathogenic effect”:
Nonspecific plaque hypothesis
According to the nonspecific plaque hypothesis, the control of periodontal disease depends on:
control of plaque accumulation
According to the nonspecific plaque hypothesis what standard of care was developed?
-oral hygiene measures
-nonsurgical/surgical debridement
The nonspecific plaque hypothesis states that all plaque are:
NOT equally pathogenic
According to the nonspecific plaque hypothesis “not all plaque are equally pathogenic”
Describe what this means regarding gingivitis:
Not all gingivitis develop into destructive periodontitis
T/F: The specific plaque hypothesis states that not all gingivitis develops into destructive periodontitis
False- this is what the nonspecific plaque hypothesis states
According to the nonspecific plaque hypothesis “not all plaque are equally pathogenic”
_____ in the pattern of disease was demonstrated in some individuals with periodontitis
site specificity
Hypothesis that states “the pathogenicity depends on the presence of or increase in specific microorganisms”
Specific plaque hypothesis
The Specific plaque hypothesis states that the pathogenicity depends on the presence of or increase in:
specific microorganisms
According to the specific plaque hypothesis _______ is localized in aggressive periodontitis
A. Actinomicetemcomitans
What was developed from the information of the Specific plaque hypothesis?
Targeted treatment strategies
Strategies that aim to control or eliminate the particular pathogenic organisms (Specific plaque hypothesis)
Targeted treatment
T/F: Pathogens may be present at the absence of disease
True
According to the Specific plaque hypothesis what bacterial species are found in the “yellow complex”:
- S. mitis
- S. oralis
- S. sanguis
According to the Specific plaque hypothesis what bacterial species are found in the “purple complex”:
- V. parvula
- A. odontolyticus
According to the Specific plaque hypothesis what bacterial species are found in the “orange complex”:
- P. intermedia
According to the Specific plaque hypothesis what bacterial species are found in the “red complex”:
- P. gingivalis
- B. forsythus
- T. denticola
According to the Specific plaque hypothesis what bacterial species are found in the “green complex”:
- E. corrodens
- C. gingivalis
- C. sputigena
- C. ochracea
- C. concisus
- A. actino. A
Hypothesis that states “both the total amount of dental plaque and the specific microbial composition of plaque may contribute”
Ecologic plaque hypothesis
The ecologic plaque hypothesis describes ______ meaning the state of the dynamic equilibrium
Microbial homeostasis
What criteria for identification of periodopathogens was formed during the nonspecific plaque hypothesis (1900s):
Kochs postulates
What criteria for identification of periodontopathogens was formed during the ecologic plaque hypothesis (1990s):
Socransky’s criteria
What criteria for identification of periodontopathogens is being described below?
-Be routinely isolated from diseased individuals
-Be grown in pure culture in lab
-Produce a similar disease when inoculated into susceptible lab animals
-Be recovered from lesions in diseased lab animals
Kochs Postulates
What criteria for identification of periodontopathogens is being described below?
-Be associated with disease
-Be eliminated or decreased in sites that demonstrate clinical resolution
-Demonstrate an alteration in host cellular or immune response
-Be capable of causing disease in experimental models
-Demonstrate virulence factors
Socranksky’s Criteria
P. gingivalis is known as a notorious periodontal pathogen. Which complex does it belong to?
Red complex
What are the virulence factors of bacteria that contribute to microbiologic specificity:
- toxins & enzymes
- Adhesins
- Evading mechanisms
Bacterial products that promote tissue destruction:
Toxins & enzymes
What are some specific toxins and enzymes that serve as virulence factors:
-LPS
-leuktotoxin
-gingipains
-collagenase
-protease
Factors that promote colonization:
Adhesins
List some specific adhesins:
-fimbria
-gingipains
The production of an extracellular capsule is an example of:
evading mechanism
What evading mechanisms functions in proteolytic degradation of host immunity components?
Gingipains
Modulating the host response via binding serum components on the bacterial cell surface is an example of:
evading mechanism
Evading mechanism that contributes to the invasion of gingival epithelial cells:
LPS
Specific bacteria of gingivitis: (8)
- Actinomyces spp.
- Capnocytophaga spp.
- Campylobacter spp.
- Streptococcus spp.
- Parvimonas micra
- Fusobacterium nucleatum
- Prevotella intermedia
- Treponema spp.
- Actinomyces spp.
- Capnocytophaga spp.
- Campylobacter spp.
- Streptococcus spp.
- Parvimonas micra
- Fusobacterium nucleatum
- Prevotella intermedia
- Treponema spp.
These bacteria are assocated with:
Gingivitis
Specific bacteria of periodontitis: (8)
- Aggregatibacter actinomycetemcomitans (Type B)
- Porphyromonas gingivalis
- Prevotella intermedia
- Parvimonas micra
- Fusobacterium nucelatum
- Tanerella forsythia
- Treponema denticola
- Spirochetes
- Aggregatibacter actinomycetemcomitans (Type B)
- Porphyromonas gingivalis
- Prevotella intermedia
- Parvimonas micra
- Fusobacterium nucelatum
- Tanerella forsythia
- Treponema denticola
- Spirochetes
These bacteria are associated with:
Periodontitis
Specific bacteria of necrotizing periodontal disease: (4)
- Fusobacterium nucleatum
- Prevotella intermedia
- Treponema spp.
- Spirochetes
- Fusobacterium nucleatum
- Prevotella intermedia
- Treponema spp.
- Spirochetes
These bacteria are associated with:
Necrotizing periodontal disease
Specific bacteria associated with pregnancy & puberty: (2)
- prevotella intermedia
- capnocytophaga spp.
- prevotella intermedia
- capnocytophaga spp.
These bacteria are associated with:
pregnancy & puberty
Specific bacteria associated with periodontal abscesses: (5)
- Fusobacterium nucleatum
- Parvimonas micra
- Prevotella intermedium
- Porphyromonas gingivalis
- Spirochetes
- Fusobacterium nucleatum
- Parvimonas micra
- Prevotella intermedium
- Porphyromonas gingivalis
- Spirochetes
These bacteria are associated with:
Periodontal abscesses
Specific bacteria of peri-implantitis is comparable to:
Microbiota to that of periodontitis
In a healthy site we see gram ____ bacteria; in a diseased site we see gram ____ bacteria
Healthy: positive
Diseased: negative
In a healthy site we see ____ bacteria shape; in a diseased site we see ____ bacteria shape
Healthy: cocci
Diseased: rod
In a healthy site we see ____ bacteria; In a diseased site we see ____ bacteria
(movement)
Healthy: nonmotile
Diseased: motile
The oxygen requirement of bacteria seen in a healthy site is ______ while the oxygen requirement of bacteria seen in a diseased site is ______
Healthy: facultative anaerobe
Diseased: Obligate anaerobe
Fermenting bacteria are seen in ____ sites, while proteolytic bacteria are seen in ____ sites
healthy; diseased
Which one is correct for the specific bacteria observed in correlated periodontal disease?
a) in diseased sites, more gram positive, nonmotile cocci are observed
b) in healthy sites, more orange and red complex bacteria are observed
c) A. actinomycetemcomitans and P. Gingivalis are highly related to periodontitis
d) Capmocytophaga spp. is usually found in periodontal abscess
C
The donor-recipient transmission of periodontal pathogens:
- Parent to child
- Spouse to spouse
T/F: Periodontal pathogens are communicable but not readily transmissible
True