Periodontal disease pathogen hypothesis Flashcards
In which century was the non-specific plaque theory the most common idea about dental plaque?
The end of the 19th century
What does the non-specific plaque theory not take into consideration?
The different levels of virulence between bacteria
When did the non-specific theory believe that disease would develop?
It believed disease would develop if threshold was reached whereby the host could no longer neutralise the the bacteria
Why is the non-specific theory still important?
Because it promotes good oral hygiene with regular supra/sub gingival removal
In which decade was the specific plaque theory developed?
the 80s
1986
What is the main argument of the specific plaque theory?
That periodontal disease were caused by SPECIFIC periopathogens
What is the Socransky complex?
Where pathogens are categorised based on their association with the severity of disease
(e.g. early colonisers, bridging species)
What was the problem with the specific plaque theory?
that the bacteria found in the red complex could also be found in healthy mouths
In what year did Philip Marsh propose the ecological plaque theory hypothesis?
1994
What does the ecological plaque theory believe disease is a result of?
They believe disease is a result of an imbalance in the total microflora due to ecological stress, resulting in the enrichment of some oral pathogens or disease-related micro-organisms
Give 3 examples of ecological changes that could affect the microflora
Presence of nutrients and essential cofactors
pH
Redox potential
What was important about Marsh’s considerations in the ecological theory?
That bacteria in the dental plaque could alter the environment, thus, allowing other bacteria to grow due to making the environment more favourable
What is the main point of the Keystone Pathogen Theory?
The keystone-pathogen hypothesis holds that certain low-abundance microbial pathogens can orchestrate inflammatory disease by remodelling a normally benign microbiota into a dysbiotic one -
i.e. increasing the quantity of the normal microbiota and changing its composition.
Give an example of a Keystone Pathogen in the Keystone Pathogen Theory
Porphyromonas gingivalis.
It has shown to be able to manipulate the innate immune system of the host.
It’s suggested that it does not only facilitate its own survival and multiplication, but of the entire microbial community.
What is the name of the latest theory that has been proposed in 2020?
IMPEDE
Inflammation-Mediated Polymicrobial Emergence and Dysbiotic Exacerbation
Model
