Aetiology & Pathology of Periodontal Disease Flashcards
(32 cards)
What is the appearance of healthy gingivae? (4)
- Pink
- Firm
- Stippled
- “Knife-edge” papillae
What are the clinical features of gingivitis? (7)
- Bleeding from gingivae
- Marginal redness
- Gingivae swollen
- No bone loss/attachment loss
- No mobility
- No Recession
- No gaps
What are the clinical features of periodontitis ? (8)
- Recession
- Mobility
- Increased probing depths (pocket formation)
- Sensitivity
- Drifting
- Gaps (Black triangles)
- Bone loss (radiographs)
- Long teeth
Define the dysbiosis plaque hypothesis
Any disruption of the ‘normal’ microbiome content that changes the symbiotic relationship between the host and microbes, a disruption that can result in disease
Define the keystone hypothesis
Certain low-abundance microbial pathogens can orchestrate inflammatory disease by remodelling a normally benign microbiota into a dysbiotic one
Describe the differences in bacteria from healthy periodontal health to periodontitis (3)
Predominant species type?
Ecological changes?
Biofilm Complexity?
- Healthy is gram positive whereas periodontitis is negative
- Healthy is aerobic, periodontitis is anaerobic
- Biofilm in healthy is simple and symbiosis, where as in periodontitis its complex and dysbiosis
Define the non specific plaque hypothesis
Plaque volume associated with level disease with the precise microbial
composition of dental plaque not critical
Define the specific plaque hypothesis
Specific species are associated with level of disease
Define the ecological plaque hypothesis
Environmental conditions dictate the balance of the microbial community
What is calculus?
- Mineralised plaque
- Calcified bacterial matrix and pellicle
Where does calculus attach?
Attaches to enamel, dentine and cementum
Describe what occurs during an initial periodontal lesion (3)
- Dental plaque accumulation
- Increased neutrophil migration
- Gingival crevicular flow increases
Describe what occurs during an early periodontal lesion (4)
- Dental plaque accumulation more extensive
- Increasing neutrophils followed by macrophages and then lymphocytes
- Increased vascularity
- Collagen destruction to create space for infiltrate
Name some bacteria found in a healthy periodontium (3)
- Streptococcus oralis
- Streptococcus mitis
- Streptococcus intermedius
Name some bacteria found in a periodontitis biofilm (3)
- Porphyromonas gingivalis
- Tannerella forsythia
- Treponema denticola
Describe what occurs during an established periodontal lesion (5)
- Neutrophils continue to migrate into the tissues and into the gingival crevice
- Extensive subgingival plaque
- Plasma cell (B cell) predominate in the
inflammatory infiltrate - No loss of CT attachment
- No bone loss
Describe what occurs during an advanced periodontal lesion (6)
- Gingival recession with fibrosis in connective tissue
- Continued extension of subgingival plaque
- Extension of inflammatory infiltrate into CT
- Apical migration and ulceration of junctional epithelium
- Periodontal ligament loss
- Alveolar bone resoprtion by osteoclasts
What triggers inflammation and immune response? (3)
- Bacterial products secreted
- Bacterial membrane
- Metabolic products
Give some examples of sentinel cells (3)
- Macrophages
- Dendritic cells
- Mast cells
What are pattern recognition receptors (PRRs) on sentinel cells are activated by? (2)
- Pathogen Associated Molecular Patterns (PAMPS)
- Damage Associated Molecular Patterns (DAMPS)
What do sentinel cells release?
Alarm molecules (alarmins) that are pro-inflammatory mediators that trigger inflammation
What is type 1 inflammation?
- Activation by histamine (Minutes)
- Vasodilatation and Endothelial cell contraction
- Inflammatory exudate move into tissues
- Leukocyte extravasation
What is type 2 inflammation?
- activation by TNF-𝛼 and IL-1𝛽 (Hours)
- More pronounced type 1 activation
- Monocyte recruitment (Macrophages in tissues)
What is the importance of RANKL on the surface of neutrophils?
Contribute to bone destruction
