Dental Plaque Biofilm Presentation PDF

Dental Plaque Biofilm Oral and Dental Sciences Rhona Mann Intended Learning outcomes By the end of the session students should be able to: Define dental plaque as biofilm Classify dental plaque and its varying locations Describe the formation of dental plaque biofilm Explain the role of...

Dental Plaque Biofilm Oral and Dental Sciences Rhona Mann Intended Learning outcomes By the end of the session students should be able to: Define dental plaque as biofilm Classify dental plaque and its varying locations Describe the formation of dental plaque biofilm Explain the role of the ‘extra-cellular slime layer to ensure bacterial colony survival Describe the contents of dental plaque biofilm Explain the most common dental disease caused by dental plaque biofilm Discuss bacterial virulence factors Discuss the most appropriate methods for dental plaque biofilm removal Definition of Dental Plaque through time now known as BIOFILM ‘Bacterial aggregations on the teeth or other solid oral structures’ ‘Soft deposits that form a biofilm Lindhe, 2003 adhering to the tooth surface or other hard surfaces in the oral cavity, including removable & fixed restorations.’ Bowen, 1976 ‘A specific but highly variable structural entity, resulting from sequential colonisation of micro-organisms on tooth surfaces, restorations & other parts of the oral cavity, composed of salivary elements like mucin, desquamated epithelial cells, debris, micro-organisms, all embedded in extracellular gelatinous matrix’ WHO, 1961 Bacteria Accessed from Accessed Google Feb www.yourdentistryguide.com 2020 This subject is linked to the following subjects Pathogen Classificat Why esis of Inflammat ion of treatment periodont ion Periodont may fail al disease al disease Year 2 – Caries Fissure Dental Caries Managem sealants Specialitie ent s Dental Plaque Biofilm – most common dental diseases Accessed from Choice Dental Accessed from The Conversation Feb 2021 Feb 2021  Coronal Classification of Dental Plaque Biofilm Supra- 1 Gingiv Marginal al Classificati on of Fissur Dental al Plaque What is the Biofilm Tooth Attach difference in ed environment 2 between Sub- Unattac supra & sub gingiv hed al that would Tissue influence attach ed dental plaque Classification of Dental Plaque Biofilm Tooth Unattache Tissue attached d attached Accessed Sharenet Feb 2020 Biofilm Definition ‘Biofilm consists of one or more communities of micro- organisms embedded in glycocalyx ( glycoprotein matrix) , that are usually attached to solid surface’ Accessed Tanninaquatics Feb 2021 Costerton et al 1994 Accessed Live Science Accessed Review of contact Feb 2021 Formation of Dental Plaque Biofilm  Initial attachment of bacteria to pellicle Four phases of Initial colonisation of dental the tooth surface – new bacteria join plaque biofilm Secondary colonisation: formation Extracellular slime layer formation Mature biofilm – mushroom shaped colonies Free-floating bacteria Biofilm formation begins when free-floating bacteria come in contact with an appropriate surface ‘put down roots’ Where is the bacteria Accessed Giphy Feb 2021 floating? Initial attachment of bacteria to pellicle Pellicle is laid down within a few hours of cleaning A thin coating of salivary proteins that attach to the tooth surface Protection of enamel from acid Double sided adhesive tape Accessed Google Feb 2021 Primary Colonisers Streptococcus sanguis Streptococcus mutans Streptococcus salivarius Accessed Google Feb 2021 Initial colonisation of the tooth surface – new bacteria join Can attach to surfaces & each other Attachment activates different genes and mediate intercellular communication – Quorums sensing (Prosser 1999). Salivary pellicle Tooth surface Quorum Sensing ( or Quorum Signalling) Process of cell to cell QS …used by bacteria to communication. form biofilms. Allows bacteria to detect and respond to cell population density by gene regulation, typically as a means of acclimatising to environmental disadvantages Secondary colonisation: Extracellular slime layer formation Production of extracellular slime layer Primary facultative colonisers start to deplete oxygen – making rooms for anaerobes Secondary colonisers attach to primary colonisers – coaggregation Salivary pellicle Tooth surface The growing bacteria grow away from the tooth Bacterial Bloom – periods Mature biofilm – mushroom shaped colonies Mushroom shaped colonies Allows for self-survival Fluid Channe Allows for own food supply ls and sewage system Salivary pellicle Tooth surface Extra-cellular Slime Layer Protective barrier that surrounds the colony Fluid Channels: Penetrate slime layer Provide nutrients, O2, movement of metabolites, waste products & enzymes Communication system – Accessed Ghostbusters Feb chemical signals 2021 Now visualise Accessed Slide Share Feb Accessed Edward Byrne Feb 2021 2021 So........ Why does plaque forms in the areas it does? Where on the crown are you least likely to see plaque? Accessed Pinterest Feb Supra vs Sub Which came first? Difference in environment? Difference in bacteria? Accessed DentalCare Sources of nutrition? Feb 2021 Shape? Composition of Dental Plaque Biofilm Composition of Dental Plaque Biofilm Organic Micro-organisms Polysaccharides Proteins Bacteria Facultative Anaerobic Glycoproteins Gram +’ve Strep. mutans Lipids Strep. Intra-cellular Matrix sanguis A. viscosus Inorganic Gram –’ve A. actinomyc P.gingivalis Calcium etemcomit ans Sodium Ekinella F.nucleatum Phosphorous corrodens Potassium P.intermedia Spirochetes T.denticola Accessed Edward Byrne Feb 2021 Micro-organisms and Oral Disease Bacteria Associated with Periodontal Disease Aggregatibacter Porphyromonas Treponema actinomycemco gingivalis denticola mitans Accessed Jornal Dentistry & Perio expertiseFeb 2021 Bacteria Associated with Caries Streptococcus mutans Lactobacilli Accessed Facebook Feb 2021 Accessed Nutraceutical Feb 2021 Bacterial Virulence Factors Refer to Virulence Factors lecture Mechanisms that enable biofilm to colonise, invade & damage tissue – VIRULENCE FACTORS Can be structural characteristics of bacteria itself or substances produced Removal of Dental Plaque What challenges do you face? Have you had someone reach for mouthwash to remove plaque? How do you explain it to a patient? How are you going to Accessed Edward Byrne Feb remove it? 2021 Physical Plaque Removal Contact with biofilm Friction Accessed Telegraph Feb 2021 Physical removal What will that do? Accessed Preferred dental Further reading https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2147593/ https://link.springer.com/article/10.1007/s10266-006-0063-3