Week 3 Flashcards
Steps in colonization of the oral cavity starting with birth?
Day 1- facultative and aerobic bacteria from birth
Day 2- anaerobic bacteria found
Day 14- mature microbiota established in gut
2 years- whole microbiota formed 10^14 total
Tooth eruption = more complex flora
Is the oral microbiota harmful?
No most are commensal and or beneficial
How much bacteria do we have in and on our bodies?
~ 2 kg
How many different types of bacteria are found in the mouth?
Over 600
When infection with a microbe happens what are the choices and how much damage happens over time?
Commensalism- no damage over time unless it gets out of control and leads to disease- in which case it damage amount goes up over time.
Colonization- damage goes up over time and can lead to clearing the infection, disease, or persistence.
Both colonization and disease can lead to persistence where damage level is constant and high over time
Disease has two outcomes: death or eradication by immune or tx
Name the 6 major ecosystems in the mouth?
- Keratinized intraoral supragingival tissue and hard surfaces
- Perio pocket (including around implants)
- Non-K tissues- buccal, palate and floor of mouth
- Dorsum of tongue
- Tonsils
- Saliva
3.
Describe plaque and the locations it is found?
Structured, layered, yellow grey,
Found on hard surfaces of teeth and restorations both above and below gums
What is materia alba?
White cheesecake like substance that is soft and easily sprayed off with water made from salivary proteins, bacteria, dead epithelial cells and some occasional food debris.
No organizational structure
What is plaque made of?
Bacteria in a matrix of salivary glycoproteins and extra cellular polysaccharides
It is a biofilm
Can plaque be removed by sprays or rinsing?
Nope impossible needs physical scraping
What is dental pellicle?
A substance that coats every surface of the mouth derived from saliva made of glycoproteins, proline rich proteins, phosphoproteins, histidine rich proteins and enzymes
Aka proteins that are a mix of glyco, phospho, histidine and proline combined with enzymes
How does dental pellicle adhere to teeth?
Electrostatic, Vanderwalls and hydrophobic forces
How fast does pellicle form after cleaning teeth?
Within nanoseconds
3 major phases of plaque formation?
- Pellicle forms
- Initial adhesion and attachment of bacteria
- Colonization and plaque maturation
Three phases of bacterial attachment?
- Random contact of bacteria with hard surface aka transport of bacteria to the tooth surface
- Initial reversible adhesion
- Attachment with a firm anchorage by reactions between bacterial adhesins and pellicle receptors
After Step 3 it needs to be scraped off aka physically removed
Which phases of bacterial attachment are non specific?
Phase 1 and 2 are random and phase 3 depends on specific interactions between bacterial surface proteins (adhesins) and pellicle receptors
Why are teeth so good at accumulating plaque?
Hard non-shedding surface to attach to
A part of our ectoderm that doesn’t shed providing a home and “port of entry” for perio pathogens
When full mouth extractions are done does the type of bacteria in the mouth stay the same?
No key perio pathogens disappear
Describe the specific location of plaque growth on teeth?
Starts at gingival margin and interdental spaces and grows toward the corona
What is Supragingival plaque?
Plaque located outside of the perio pocket that starts at the gingival margin (touch’s the margin)
What type of bacteria makes up the first layer (touching the tooth) of supragingival plaque?
Gram positive cocci and short rods
What type of bacteria makes up the outer layer (surface) of supragingival plaque?
Gram negative rods and filaments, spirochetes
What is a major factor is causing plaque to stick to the surface of teeth?
The roughness of the surface.
Fine polishing paste or glycine powder for air polishing
What does thicker plaque contain and is it more or less pathogenic?
More pathogenic
Contains more motile bacteria like spirochetes and is packed denser so more organisms
What areas of the mouth does plaque form the fastest?
Lower, interproximal, buccal areas of molars…
IP is faster than straight buccals and lower molars traps food easier
Does plaque form at the same rate on people?
Nope varies a lot
What can explain 90% of the variations in the rate of plaque formation?
Salivary induced aggregation and relative flow
Does more or less saliva cause plaque to form faster?
More saliva= faster
Other than amount of saliva what are some other factors in plaque formation?
Diet, Chewing fibrous foods, Smoking, Brushing tongue and palate, Antimicrobial factors in saliva, Inflamed gingiva
Does age influence plaque formation?
No
Does plaque in older or younger people leave to more gingivitis?
Older
Does eating remove plaque?
Nope
What makes sub gingival plaque different?
Different environment,
Availability of blood products and an anaerobic environment
Do strict anaerobes contribute to initiation of periodontal disease?
Most likely very little but it is under debate
Not sure yet what exactly causes the consequences of the disease
Can sub gingival plaque be removed completely?
No it is really hard to do so
What is left allows for recolonization
Can some sub gingival plaque pathogens penetrate soft tissue and dentin?
Yes they can
How fast does sub gingival plaque recolonize after a cleaning?
7 days it is back to pretreatment levels
How does tooth associated sub gingival plaque versus tissue associated sub gingival plaque vary throughout the pocket?
Tooth associated subgingival plaque is more like Supragingival plaque than tissue associated.
What bacteria does TISSUE associated sub gingival plaque contain?
Mostly- gram negative rods and cocci
Others- filaments, flagellated rods and spirochetes
Do plaque colonies share resources?
Yes there are fluid channels that nutrients run though
Plus they communicate with each other via quorum sensing
What binds lower layers of plaque together?
Polysaccharide matrix with both organic and inorganic materials
Can perio and cariogenic pathogenic bacteria be transmissible to other people?
Yes both are transmissible- most common is vertical transmission in families.
Familial horizontal is less common
Can pathogenic bacteria be translocated from one place in the mouth to another?
Yes is can be spread with things like proxa brushes
List non bacterial organisms that live in the mouth too?
Viruses,
Fungi/yeast,
Protozoa,
Archaea
3 plaque hypotheses that have been discarded by now?
- Non-specific plaque hypo- control plaque and you control the disease
- Specific plaque hypo- only certain plaque is bad and if you have it then you get the disease
They still didn’t know if it was causal or correlation - Ecological plaque hypo- little deeper both plaque levels and specific bacteria along with the disease along with some host factors
What is the current accepted hypothesis on perio and plaque?
Keystone Pathogen Hypothesis
What does the Keystone Pathogen Hypothesis say?
A specific pathogen P. gingivalis is present in low numbers but it can disrupt the perio microbiota leading to dysbiosis.
What type of bacteria is associated with health?
Mostly Facultative- Gram positive rods and cocci
With a few anaerobic both pos and neg rods along with positive cocci
What type of bacteria is associated with gingivitis?
Main point- The levels of anaerobic bacteria gram negative rods and facultative gram negative rods increases
There are gram positive rods and cocci around along with negative cocci
Extra details-
Levels of facultative gram + rods and cocci decrease
Small amounts of anaerobic + cocci turn into - cocci
Anaerobic + rods decrease
What type of bacteria is associated with periodontitis?
Anaerobic gram negative rods 75%
Anaerobic gram positive rods ~12%
Spirochetes as well now
The rest are facultative gram positive rods and cocci
Take away- during gingivitis anaerobic gram neg rods increase in numbers along with facultative gram neg rods then the anaerobic neg rod take over in Periodontitis
90% of the bacteria present in Periodontitis is anaerobic
Gram positive rods and cocci = good
What does the rate of plaque growth on unbrushed teeth look like?
Exponential at first
First 24 hrs slow,
Next 3 days rapid
After 4 days it slows and shifts to anaerobic and gram negative
How much of the bacteria present is periodontitis is anaerobic
Most approximately 90%
List common bacteria associated with gingivitis names?
Don’t have to know this yet but made this card to start to get familiar with them.
Gram +: streptoccus, actinomyces, eubacterium and parvimonas
Gram - : capnocytophaga, fusobacterium, prevotella, campylobacter gracilis, C. consisus,B. parbula, E. corrodens
List common bacteria associated with periodontitis names?
Don’t have to know this yet but made this card to start to get familiar with them.
P. gingivalis, T. forsythia, P. intermedia, C. rectus, E. corrodens, F. nucleatum, A. actinomycetemcomitans, T. denticola
Which bacteria is associated with early (age) localized aggressive bone loss?
A. actinomycetemcomitans
A.a. May make up 90% of bacteria found in pockets
Generalized aggressive periodontitis is dominated by what kinds of bacteria?
GIFT AA or A GIFT
P. gingivalis, P. intermedia, T. forsythia, treponema spp., And less A. actinomycetemcomitans
Necrotizing perio disease is associated with what systemic disease?
HIV
In necrotizing periodontitis what types of bacteria are associated?
P. intermedia and spirochetes
What is the tx for necrotizing perio disease?
Debridement,
OHI,
Mouth rinse and pain meds,
If no response to the above then-
Antibiotics
When do perio abscesses occur?
Untreated perio or sometimes right after srp usually
Foreign matter gets stuck under gum tissue- popcorn kernels
Symptoms of a perio abscess?
Pain, swelling, suppurations(puss), BOP and mobility
What is the tx of a perio abscess?
Clean it out
Bacteria associated with a perio abscess?
F. nucleatum, P. intermedia, P. gingivalis, P. micros, T. forsythia
When perio is a manifestation of a systemic disease is it specific bacteria or due to immune response issues?
Immune response defects
When perio is a manifestation of a systemic disease what are some potential immune response issues?
Neutrophils defects,
Leukocytes adhesion defects
Severe destruction may be associated w/ mutation of the Cathepsin C receptor
5 benefits of good bacteria?
- Passively occupy a niche
- Limit bad or pathogenic bacteria’s ability to adhere to tissue surfaces
- Adversely affect growth or vitality of pathogen
- Affect the ability of pathogen to produce virulence factors
- They degrade pathogenic virulence factor
Drawbacks to microbial testing?
Presence of Pathogens doesn’t = disease
Pathogens detected in healthy people
Quality of host response isn’t looked at
Are biofilms resistant to antibiotics?
Why or why not? How much more o less?
Yes 1000-1500 times more resistant
Antibiotics can’t reach inner film easily meanwhile outlayer is passing along mutations for for resistance, differences in growth rates, nutrition and pH can all affect the effectiveness of antibiotics
What is calculus and where does it form?
Mineralized plaque on hard surfaces of natural teeth both sub- and supra-gingival and prosthetics
How common is calculus?
- 9 % has supragingival
- 1 % has subgingival
Probably more
What % of calculus is inorganic and what is the composition of the inorganic part?
70-90%
76% calcium phosphate, 3% calcium carbonate, 4% magnesium phosphate and other metals.
Another way to break it down is 2/3rds of the inorganic are crystalline: Hydroxyapatite, Magnesium whitlockite, Octocalcium phosphate Brushite
Does calculus have more or less inorganic mass than bone, enamel and dentin?
More than bone and less than enamel…. In order most to least- 1. Enamel 96% 2. Calculus 70-90% 3. Bone 60-70% 4. Dentin 45%
How does calculus form?
By precipitation of mineral salts on the the inner layer of plaque in layers and subsequent calcification
When does calculus formation and calcification happen?
Precipitation for mineralization starts between 1 and 14 days of plaque formation and calcification/initial hardening can start in as little as 4-8 hours
Why does calculus form?
Local rise in saturation of calcium and phosphate ions
Rise in pH causes precipitation,
when pH rises colloidal proteins settle out of saliva leading to precipitation
Different out comes in a mouth based on high or low pH?
Acid is caries and basic is calculus
What are the 4 methods of calculus attachment to teeth?
- Attaches to pellicle-no need bacteria
- Mechanical- locks in to surface irregularities
- Close adaptation of calculus under surface depressions of cementum
- Calculus bacteria penetrate into cementum
Basics of supragingival calculus location, make up, color, timing?
Gingival margins near salivary ducts
Minerals from saliva
Whitish yellow
Forms in less than 24 hrs
Moderately hard but removable
Dry to see
Mineral source for sub gingival calculus ?
Gingival crevicular fluid and inflammatory filtrate
Location of sub gingival calculus?
All over but most common in interproximal areas
Color of sub gingival calculus?
Brown or black
How hard is subgingival calculus?
Dense, hard and tenacious
How fast does subgingival calculus form?
Slower that supra
Can we distinguish between the effects of plaque and calculus?
It is difficult- calculus is always covered in plaque
Is calculus correlated with gingivitis?
Yes
Cornerstone of periodontal therapy?
Removal of plaque and calculus
4 perio risk categories?
- Risk Factors
- Risk Determinants/background characteristics
- Risk Indicators
- Risk Markers or Predictors
3 Risk factors?
- Tobacco smoking,
- Diabetes,
- Pathogenic bacteria and microbial tooth deposits
5 Risk Determinants/ Background Characteristics?
- Genetic factors,
- Age,
- Gender,
- Socioeconomic Status,
- Stress
3 Risk Indicators?
- HIV/ AIDS
- Osteoporosis
- Infrequent Dental Visits
2 Risk Markers or Predictors?
- Previous history of perio disease
2. Bleeding on probing
What is risk assessment?
Probability that a person will develop a disease in a given time period
Basics of what makes a risk factor?
Environmental, behavioral or biological
Identified by longitudinal studies
Exposure at single point, multiple or continuous prior to onset of disease
Intervention helps
What percent of perio cases are smokers?
42% current and 11% past smokers
Current smokers are 3x more likely to have perio disease than non
Does smoke more increase the risk?
Yes heavy smokers have higher rates of severe perio
Does risk decrease with years since a smoker quit?
Yes
Are the negative effects of smoking on gingivitis reversible?
Yes it can be cleared up perio on the other hand can be treated and stopped but not actually reversed
Do former smokers respond well to perio therapy?
Yes they respond similar to non-smokers
Effects of smoking on the microbiology of the mouth in regards to periodontitis?
Increases complexity and negatively effect periodontitis associated pathogen colonization both sub and supragingival
What does smoking do to oral immune and inflammatory response? 4 things
- Alters neutrophil chemotaxis, phagocytosis and oxidative burst
- Increases tumor necrosis factor alpha and prostaglandin E2 in GCF (gingival crevicular fluid)
- Increases collagenase and elastase in GCF
- Increases prostaglandin E2 by monocytes in response to lipopolysaccharide
What does smoking do to a persons physiology ? 4 things
Masks some key indicators of gingivitis and periodontal disease
- Decreases gingival blood vessels but increases inflammation
- Decreases GCF flow and bleeding but increases inflammation
- Decreases subgingival temperature
- Increases time need to recover from anesthesia
What are the 5 A’s to use with patients who smoke?
- Ask if they smoke
- Advise of the association between oral disease and smoking
- Assess their interest in quitting
- Assist them in quitting
- Arrange a referral or follow up care
What is diabetes?
A metabolic disease characterized by chronic hyperglycemia with a direct relationship to periodontal disease
Is there a difference in perio risk between type I and type II?
Nope
Where does perio disease rank in regards to common complications of diabetes?
6th most common complication
4 things that happen in poorly controlled diabetes?
- Altered immune function in PMNs
- Qualitative changes in bacteria
- Altered collagen structure and function
- All this leads to severe gingival inflammation, deep pockets, rapid bone loss and perio abscesses
3 perio rate differences between diabetics and non-diabetics?
Type 1 teenagers = 5x
Poorly control adults = 2.9x
Smoker and poorly controlled = 4.6x
Do uncontrolled diabetics respond well to periodontal therapy?
No they have a poor response compared to both controlled and non diabetics
Does clinical attachment loss increase with age in diabetics?
Yes
What is important composition or quantity of plaque regarding it as a risk factor for perio disease?
Composition
Name 3 bacteria commonly associated with perio disease?
A. actinomycetemcomitans
P. gingivalis
T. forsythia
7 anatomical factors that harbor plaque?
- Furcations
- Root concavities
- Grooves
- Cervical enamel projections
- Enamel pearls
- Overhanging margins or restorations
- Calculus
What are Risk Determinants/Background Characteristics ie general definition?
Risk factors that is non modifiable aka can’t change
Name 5 Risk Determinants?
- Genetic factors,
- Age,
- Gender,
- Socioeconomic Status,
- Stress
Have studies shown a link to perio disease in genetics?
Yes twin studies and Sri Lanken Tea worker
What genetic factors have shown to be linked to severe perio?
Alterations in IL-1 genes
Alterations in neutrophils
and monocytic hyper responsiveness associated with severe perio
How does age affect perio?
Increase prevalence with age most likely due to an increase in exposure to other risks and cumulative destruction
Who has higher rates of perio disease- men or women and why?
Men most likely not as good preventative practices
How is socioeconomic status linked to perio?
Lower has higher rates of perio
Maybe less education, lack of dental visits, lack of hygiene since other things like staying alive matter more
How is stress linked to perio?
Higher stress decrease immune function
Periodontal disease has been shown to occur at higher rates during periods of high stress
General definition of Risk Indicators?
Probable risk factors identified in cross-sectional not longitudinal studies
Name 3 Risk Indicators?
- HIV/AIDS
- Osteoporosis
- Infrequent dental visits
What is a prominent diagnostic feature of HIV associated perio disease?
Oral lesions
7 oral manifestations of HIV?
- Oral Candidiasis
- Linear gingival erythema
- Oral hairy leukoplakia
- Kaposi sarcoma and other malignancies
- Acute necrotizing ulcerative gingivitis
- Necrotizing ulcerative gingivitis and periodontitis
- Chronic periodontitis
How is osteoporosis linked to periodontal disease as a Risk Indicator?
Doesn’t initiate it
Studies are conflicting
But bone density loss may aggravate perio progression
Do studies agree on Infrequent Dental Visits as a Risk Indicator?
No some say yes and some no
What is the general definition of what defines a Risk Marker or Predictor?
They are things associated with perio disease but do not cause it
Name 2 Risk Markers?
Previous perio disease predicts future unless well controlled
Bleeding or absence of bleeding on probing
But careful of probing force and bleeding- hard probing can cause bleeding in healthy people
Is bleeding on probing a good predictor for perio disease or absence of it a good predictor for perio health?
Continuous absence of BOP is a reliable 98% predictor for maintenance of perio health
Positive prediction of disease was only 6%
ie people bleed at times for many other reasons than perio and that doesn’t mean perio disease but not bleeding does mean you are healthy
Pathway of clinical assessment?
- Medical History, dental history, physical perio exam
- Identify Risks from the 4 categories
- Make tx decisions
- Treat and assess response
- Then either maintain or reassess risks and start again
What should always be a part of any risk assessment and intervention/treatment strategies?
Patient Education!
Does plaque form faster next to inflamed or healthy gingiva?
Inflamed
On a general level how do plaque bacteria vary in the perio pocket by depth?
Deeper part of pocket is less filamentous,
The apical portion is dominated by smaller bacteria in no particular orientation
