The Oral Microbiome, Biofilms, Gingivitis and Periodontitis Flashcards
Explain the symbiosis of man and microbes?
Healthy digestive tract Resistance to colonisation of pathogens Regulates CVS Support host defence Anti-inflamm properties Additional metabolic potential Antioxidant activity
Name and explain different types of respiration?
Aerobic: in oxygen Obligate aerobes: require oxygen Obligate anaerobes: killed by oxygen - o2 final electron acceptor - fermentation Facultatice anaerobes: tolerate oxygen and switch to co2 Capnophilic: preferes co2
Saliva functions?
ADD
Biofilm definition?
Community of microbes characterised by cells that are attached to a surface or to each other and embedded in a matrix of extracellular polymeric substances
Process of biofilm formation - bacterial formation and development?
Bacteria approach surface Contact and attachment Adherence and change in cell surface Metabolic activity changes environment Quorum sensing and development Mature biofilm can seed new cells into environment
Number of bacterial species? Genus examples?
770 Streptococcus Staphylococcus Bacillus Aspergillus
Number of fungal species? Genus examples?
9-23
Candida
Saccharomycrs
Aspergillus
Viruses? Oral examples?
Herpes 90%
HPV 25%
Priming of microbiome may originate in-uterine?
Process of priming?
Loosen of epithelial cells due to preg hormone (bacterial penetration)
Bacteria reach lamina propria and vasc tissue
Transfer bac to placenta via bloodstream
Oral bac trapped in placenta tissue
PACs acquire the allergenic info in placenta
APCs return to feral peripheral lymphoid organ
Fetal T regs recognised maternal microbiome as safe and generated in fetal lymphoid tissue
Bacteria in buccal mucosa?
Streptococcus
Bacteria in hard palate?
Streptococcus
Bacteria in keratinsied gingiva?
Streptococcus
Bacteria in saliva?
Streptococcus
Porphyromonas
Bacteria in sibgingival plaque?
Strep
Fusobacterium
Prevotella
Bacteria in supragingival plaque
Strep
Fuse
Coryne
Bacteria in throat?
Strep
Bacteria on tongue?
Strep
Species of streptococcus?
Mutans: Alpha haemolysis, mutans, sobrinus, cricetus, dental caries
Salivarius: alpha, salivarius, vestibularius, keratibised surfaces and vestibule mucosa
Oralis: alpha, borealis, sanguis, mitis, gordonii and cristacus, early colonisers produces glucans, non-kerat, dental plaque
Anginosus: beta, anginosus, intermedius and constellatus, purulent infections (abscesses)
Factors which cause the shift from symbiosis and dysbiosis?
Major ecological pressures
Inflammation
Increased temperature or pH
Diet and reduces pH
Carbohydrate sources?
Glucose Fructose Sucrose Lactose Galactose Mannose Celliobiose B-glucosides Trehalose Maltose Raffinose Ribulose Starch
Pellicle? Description? Characterisitics?
The layer of material acquired by a cleaned tooth
- mucin, proline rich proteins, statherin and amylase (lysozyme, albumin, Ig, glucans)
Prerequisite for bacterial attachment
Structure of pellicle?
90% salivary glycoproteins
- d domain, cys rich, O-glucans (VNTR) and cys rich
Proline rich proteins? Characterisitics?
Acidic 16kD: saliva, affin for hydroxyapatite, Ca and PO4 levels and antibacterial activity
Basic 6-9kD: saliva and nasal secretions, complex with tannin
Glycosylated 36kD: newly formed pellicle
Alpha amylase?
Alpha 1-4 glycosidic bonds Digestive function of starch and amylase Essential component of salivary pellicle Bacterial receptor Forms heterotypic mixed micelle like structure
Bacterial adhesion?
Pellicle at the enamel allows adhesion to a bacteria, that can form a chain of bacteria
Stages of development in plaque biofilm?
Start: Clean enamel surface 2s: Pellicle formation 1m: Pioneer bacteria (strep sangius) 2h: icrocolones and extracellular polysaccaride > 2h: biofilm 48h: mature plaque 2-7d: microbial succession and diversification > 7d: climax community
Dysbiosis? Definition?
A condition in which the normal microbiome pop structure is disturbed often through external burdens such as disease states or medications
Holobiont? Defintion?
Host organism and all its symbiotic microbial resident
Microbiome? Defintion?
Sum of microbes and their genetic information and the environment in which they interact
Symbiosis? Defintion?
Two or more species living closely together in a long term relationship
Biofilm related diseases?
Periodontal disease
Dental caries
Assessing a person’s health?
By frailty
What does the oral healthcare team gave to consider?
Weight loss, smoking cessation, exercise and controlling disease and glycaemia
Educational programmes? Professional targets?
Mothers to be
New mothers
Care home workers
People whom have dependable people
Dental check ups? Key touch points?
2, 5, 12, 26, 40 and 70
Toothbrush storage? Location and why?
Separately in bathroom to avoid horizontal transmission
Saliva levels? Why?
Oral microbiome
Bacteria colonisation? Location?
Teeth, gingival crevice and hard palate
Dental biofilm? Defintion?
Masses of microorganisms that bind to and multiply on a solid surface, typically with a fluid bathing thr microbes
Free flowing microorganisms are called planktonic cells
These communities form microcolonies and interact with each other (quorum sensing)
Acquired salivary pellicle? Characterisitics?
Thin layer Forms on teeth within seconds Smooth, colourless and translucent Bacteria free Derived from salivary glycoportrind Affinity for hydroxyapatite
Initial stage of biofilm formation?
Attachment of acquired pellicle, which is a thin coat of salivary glycoprots, to a clean tooth surface
Bind to buccal, but list due to desquamantion
Non-shedding surfaces permit extensive development (plaque at retention sites)
- susceptibility for disease
Acquired pellicle formation? Host and bacterial origin?
Host: - glycoprot, phosphoprot, statherin, amylase, protein rich peps, and host defence components
Bac: - glucotransferase and glucan
Oral habitats? Location and characterisitics?
Buccal mucosa: - sparse, desquamates and masticatory friction
Dorsum tongue: - highly, rough papillary surface, refuge, reservoir for -ve, low redux potential (anaerobic)
Crevicular epith: - pioneer bacteria for initiation, and development of gingival and periodontal disease
Dentures, restorations and orthodontic
Tooth surfaces: supra and subgingival (non-shed)
Teeth as a habitat? Characteristics?
Only non-shed area of the oral cavity
Masses of bacteria constantly accumulate at surface to produce biofilm
Biofilm is the initatiting factor in caries and periodontal disease
Shoft from symbiotic to dysbiotic