Etiology Flashcards
What are the two basic forms of periodontal disease?
Gingivitis
Periodontitis
Reversible, inflammation confined to the gingival tissues is called?
Gingivitis
Inflammation that is not confined to gingiva and involves attachment apparatus is called?
Periodontitis
What three general factors contribute to periodontal disease?
Microbial plaque
Genetics
Acquired/environmental factors
Where do most things that enter the free gingival sulcus come through?
Junctional epithelium
How much time without hygiene is needed to see the onset of gingivitis?
10-21 days
With hygiene how quickly can gingivitis resolve?
1 week
What are the main 5 microbes in plaque?
Bacteria Fungus Protozoa Virus Mycoplasm
What does calculus provide for plaque?
Attachment surface
What is quorum sensing in a biofilm?
Microbes sensing how many other microbes are in the biofilm
What do early biofilm colonizers recognize?
Glycoproteins on the surface of the tooth
Which 3 bacteria are in the red complex?
- porphyromonas gingivalis (G-, non motile)
- tannerella forsynthesis (G-, non motile)
- treponema denticola
What makes the acquired Pelicle on teeth?
Glycoproteins in saliva
What are the 6 common infection types in the oral cavity?
- caries
- periapical lesions
- fungal
- viral
- abcesses
- periodontal
Where does the majority of dental and periodontal disease originate?
in the inter proximal area
What is a virulence factor?
Property that enables the bacterium to cause disease
what is the purpose of Fimbrea, Pili and fibrillae?
Bacterial attachment, prevention of phagocytosis
What is the purpose of a capsule?
Protection, attachment, prevention of phagocytosis
Where does endotoxin come from?
Gram negative bacteria when they die. It is a lipopolysaccharide which makes it hard to break down
What results from the presence of endotoxin?
activation of inflammatory response, cytokine production and bone resorption
Roughly how long does it take for pathogenic flora to develop?
42 days
why do bacteria try to attach to the tooth/pelicle?
to avoid being flushed out by the positive pressure created by gingival crevicular fluid
How is virulence factor defined?
ability to adhere
What two ways can bacteria enter the host?
- ulcerations in the epithelium
- direct penetration in the host tissue (less common)
What is the formula for periodontal disease?
Pathogenic flora+ Lack of beneficial bacteria+susceptible host= Periodontal disease
What are 7 common periodontal pathogens?
1-Aggregatibacter actinomycetemcomitans (AA) 2- Porphyromonas gingivalis 3- Prevotella intermedia 4- Tannerella forsythia 5- Fusobacterium nucleatum 6-Peptostreptococcus micros 7-campylobacter rectus
What are 5 examples of beneficial oral bacteria?
1-Actinomyces spp. 2-Strep mitis 3- Strep sanguis 4- Capnocytophaga spp. 5- V. Parvula
What are 7 common ways for a host to be more susceptible?
1-Impaired neutrophils 2-inadequate immune response 3-LPS responsiveness 4-AIDS 5-Diabetes 6-Smoking 7-Drugs
Define Pellicle formation
A thin, Bacteria-free layer of salivary proteins attached to the tooth surface within minutes of a professional cleaning
How quickly does attachment of bacteria occur after a cleaning?
Within hours
What are the two major types of plaque?
- Supragingival plaque
- subgingival plaque
What are the two major types of supra gingival plaque?
Coronal plaque
marginal plaque
Attached sub gingival plaque is found where?
tooth, epithelium and connective tissue
Where does unattached sub gingival plaque reside?
in the gingival crevicular fluid
What is calculus?
Dead, mineralized plaque
Unattached sub gingival plaque consists main of what type of bacteria?
Gram-negative, motile bacteria
Young supra-gingival plaque is mainly what type of bacteria?
gram + cocci and rods
Aged supra-gingival plaque is mainly what type of bacteria?
gram - anaerobic bacteria
What 5 things are characteristic of Supragingival plaque?
1-50% matrix 2-mostly gram + 3-Few motile bacteria 4-aerobic unless thick 5-metabolizes carbohydrates
What 5 things are characteristic of sub gingival plaque?
1-Little or no matrix 2-mostly gram - 3-commonly motile bacteria 4-anaerobic 5-metabolizes proteins
What is characteristic of Aggregatibacter actinomycetemcomitans?
- small non-motile
- gram negative
- facultative anaerobe
- saccharolytic
- coccobacillus
- colonies have star shaped center
- many serotypes
What do endotoxins do?
- can kill PMNs
- cytotoxic effects
- bone resporption
What is characteristic of porphyromonas gingivalis?
- gram negative
- anaerobic
- non motile
- asaccharolytic
- rod shaped
- black pigment due to broken down hemoglobin
- invades epithelial cells
- able to grow at elevated pH
- capsule
what is characteristic of tanerella forsythia?
- gram negative
- anaerobic
- spindle shape
- pleomorphic
- invades epithelial cells
What is characteristic of prevotella intermedia?
- black pigment
- gram negative
- anaerobic
- short rounded end rod
- elevated in ANUG
What is characteristic of fusobacterium nucleatum?
- gram negative
- anaerobic
- spindle shaped
- most common isolate from sub gingival samples
What is characteristic of campylobacter rectus?
- gram negative
- anaerobic
- short motile vibrio
- small convex colonies on blood agar
- produces leukotoxin
What is characteristic of peptostreptococcus micros?
- gram positive (only one)
- anaerobic
- small coccus
- asaccharolytic
What is characteristic of spirochetes?
- gram negative
- anaerobic
- helical shape
- related to ANUG
