Dental Plaque Biofilm PDF

Dental Plaque Bio.lm Oral and Dental Sciences Rhona Mann Intended Learning outcomes By the end of the session students should be able to: De#ne dental plaque as bio#lm Classify dental plaque and its varying loca9ons Describe the forma9on of dental plaque bio#lm Explain the role of the ‘...

Dental Plaque Bio.lm Oral and Dental Sciences Rhona Mann Intended Learning outcomes By the end of the session students should be able to: De#ne dental plaque as bio#lm Classify dental plaque and its varying loca9ons Describe the forma9on of dental plaque bio#lm Explain the role of the ‘extra-cellular slime layer to ensure bacterial colony survival Describe the contents of dental plaque bio#lm Explain the most common dental disease caused by dental plaque bio#lm Discuss bacterial virulence factors Discuss the most appropriate methods for dental plaque bio#lm removal  De.niFon of Dental Plaque through Fme now known as BIOFILM ‘Bacterial aggregations on the teeth or other solid oral structures’ ‘So$ deposits that form a bio2lm adhering to Lindhe, 2003 the tooth surface or other hard surfaces in the oral cavity, including removable & 2xed restora=ons.’ 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 www.yourdenFstryguide.com Accessed Google Feb 2020 2024 This subject is linked to the following subjects Pathogenesis Why Classi.caFon of periodontal treatment InSammaFon of Periodontal disease may fail disease Year 2 – Caries Fissure Caries Dental Management sealants SpecialiFes Dental Plaque Bio.lm – most common dental diseases caries periodontitis Accessed from Choice Dental Accessed from The ConversaFon Feb 2021 Feb 2021  Coronal Classi.caFon of Dental Plaque Bio.lm Supra- 1 Marginal Gingival aerobic Classi.caFon Fissural of Dental Plaque Bio.lm What is the Tooth di[erence in AZached environment 2 between supra & Sub- UnaZached sub that would inSuence dental Aneric gingival plaque Tissue aZached composiFon? Oxygen. Classi.caFon of Dental Plaque Bio.lm Tooth aZached UnaZached Tissue aZached in contact damaging In contact more around with Soft with hard Tissue · Accessed Sharenet Feb tissue resiliand+ adapt. 2020 Bio.lm De.niFon ‘Bio2lm consists of one or more communi=es of micro-organisms embedded in glycocalyx ( glycoprotein matrix) , that are usually aDached to solid surface’ Costerton et al 1994 Accessed TanninaquaFcs Feb 2021 Accessed Live Science Feb 2021 Accessed Review of contact lenses Feb 2021 FormaFon of Dental Plaque Bio.lm  IniFal aZachment of bacteria to pellicle Four phases of IniFal colonisaFon of the dental tooth surface – new bacteria join plaque bio.lm Secondary colonisaFon: formaFon Extracellular slime layer formaFon Mature bio.lm – mushroom shaped colonies Free-SoaFng bacteria Bio#lm forma9on begins when free-Aoa9ng bacteria come in contact with an appropriate surface ‘put down roots’ Where is the bacteria SoaFng? In the mouth. Accessed Giphy Feb 2021 IniFal aZachment of bacteria to pellicle Pellicle is laid down within a few hours of cleaning A thin coa9ng of salivary proteins that aEach to the tooth surface Protec9on of enamel from acid Double sided adhesive tape Accessed Google Feb 2021 Primary Colonisers Streptococcus sanguis Streptococcus mutans Streptococcus salivarius Accessed Google Feb 2021 IniFal colonisaFon of the tooth surface – new bacteria join Can aEach to surfaces & each other AEachment ac9vates diHerent genes and mediate intercellular communica9on – Quorums sensing (Prosser 1999). Salivary pellicle Tooth surface Quorum Sensing ( or Quorum Signalling) Process of cell to cell QS …used by bacteria to form communica9on. bio#lms. Allows bacteria to detect and respond to cell popula9on density by gene regula9on, typically as a means of acclima9sing to environmental disadvantages Secondary colonisaFon: Extracellular slime layer formaFon Produc9on of extracellular slime layer Primary faculta9ve colonisers start to deplete oxygen – making rooms for anaerobes Secondary colonisers aEach to primary colonisers – coaggregaFon The growing bacteria grow away Salivary pellicle from the tooth Tooth surface Bacterial Bloom – periods of accelerated bacterial growth Mature bio.lm – mushroom shaped colonies Mushroom shaped colonies Allows for self-survival Fluid Channels Allows for own food supply and sewage system Salivary pellicle Tooth surface Extra-cellular Slime Layer Protec9ve barrier that surrounds the colony Fluid Channels: Penetrate slime layer Provide nutrients, O2, movement of metabolites, waste products & enzymes Communica9on system – chemical Accessed Ghostbusters Feb 2021 signals Now visualise Accessed Slide Share Feb 2021 Accessed Edward Byrne Feb 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 2021 Supra vs Sub Which came.rst? Di[erence in environment? Di[erence in bacteria? Accessed DentalCare Sources of nutriFon? Feb 2021 Shape? ComposiFon of Dental Plaque Bio.lm ComposiFon of Dental Plaque Bio.lm Organic Micro-organisms Polysaccharides Proteins Bacteria FacultaFve Anaerobic Glycoproteins Gram +’ve Strep. mutans Strep. sanguis Lipids A. viscosus Intra-cellular Matrix Gram –’ve A. ac9nomycet P.gingivalis Inorganic emcomitans Calcium Ekinella F.nucleatum corrodens Sodium P.intermedia Phosphorous Spirochetes T.den9cola Potassium Accessed Edward Byrne Feb 2021 Micro-organisms and Oral Disease Bacteria Associated with Periodontal Disease Porphyromonas AggregaFbacter Treponema denFcola gingivalis acFnomycemcomitans Accessed Jornal DenFstry & Perio experFseFeb 2021 Bacteria Associated with Caries Streptococcus mutans Lactobacilli Accessed Facebook Feb 2021 Accessed NutraceuFcal Feb 2021 Bacterial Virulence Factors Refer to Virulence Factors lecture Mechanisms that enable bio#lm to colonise, invade & damage 9ssue – VIRULENCE FACTORS Can be structural characteris9cs 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 paFent? How are you going to remove it? Accessed Edward Byrne Feb 2021 Physical Plaque Removal Contact with bio#lm Fric9on Accessed Telegraph Feb 2021 Physical removal What will that do? Accessed Preferred dental care Feb 2021 Further reading hEps://www.ncbi.nlm.nih.gov/pmc/ar9cles/PMC2147593/ hEps://link.springer.com/ar9cle/10.1007/s10266-006-0063-3