Ahmed , 20year old patient comes to your clinic and asks       you, what is white stuff on my teeth, and will it affect my...
Consists of a                                                                     What is it made up of ?        - surface...
Function & Clinical Significance Of Dental                       Pellicle     Protective functions                        ...
Dental plaque/Dental Biofilms        The soft, non-mineralised deposit which forms on                C.    Presence of pel...
What is the clinical appearance of                                                     Thus a dental biofilm = a diverse c...
Bacteria in dental biofilm                                        Structure of dental biofilm        more than 500 differe...
Types of plaque (location)                                          To cope within a hostile environment micro-organisms m...
The Extracellular Polysaccharides (EPS) are:    What are the properties of dental biofilm ?     a. Micro-organisms are arr...
How does dental biofilm form ?                                              Bacterial colonisation of the mouth     Stage ...
This process is rapid                                                                                      beginning soon ...
Stage 3 of dental biofilm formation.                                                                     Rapid bacterial g...
Characteristics of Mature Dental Biofilm         Mature plaque      - more G-ve (don’t attach initially due to poor       ...
Factors affecting accumulation of dental biofilm         Ability to colonise         Saliva - influences pellicle formatio...
Ability to reduce plaque levels – How can we     Clinical detection of dental biofilms                                    ...
Removal of dental biofilm         Not with water or rinsing alone         Mechanically needs to be removed by          -  ...
Dental Caries      Dental caries                                                      Plaque is an important factor in the...
Subgingival calculus presents as a black-                            brownish hard mass if the gingival margin            ...
Materia Alba = ‘white matter’                            Food Debris      Consists of                                     ...
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Dental deposits [compatibility mode]

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Dental deposits [compatibility mode]

  1. 1. Ahmed , 20year old patient comes to your clinic and asks  you, what is white stuff on my teeth, and will it affect my  white stuff on my teeth, and will it affect my  teeth or gums ?” Dr.Abeer Abdul Sattar D Ab  Abd l S tt DCP 1 DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 2 DR.ABEERABDUL SATTAR 1 Acquired pellicle Dental Deposits a thin coating of salivary 1. Acquired pellicle origin, found on all 2. Dental plaque/biofilm exposed tooth surfaces 3. Dental calculus Can also form on other 4. Food debris surfaces such as glass 5. Materia Alba beads, filling materials, dentures and celluloid strips placed on teeth. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 4 DR.ABEERABDUL SATTAR 31
  2. 2. Consists of a What is it made up of ? - surface layer - the initial film - Composed of salivary glycoproteins – long chain - sub-surface layer - is protein rich and fills the small cracks/voids and defects in the enamel surface. CHO’s and protein units – amino acids - Amorphous (no set structural pattern) - (glycoproteins also called mucins) - Homogenous (uniform throughout) - Organic layer - It is very thin - Co a s no ce s (ace u a – co a s no minerals Contains o cells (acellular contains o e as and no bacteria) DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 6 DR.ABEERABDUL SATTAR 5 Formation Of Dental Pellicle a. Spontaneous just occurs, bacteria are not     neccesary Oral fluids/molecules can diffuse through the b. Bacteria not necessary (forms in germ free animals) Is acellular (contains no bacteria). aquired pellicle into the superficial enamel Clinical appearance c. Forms from salivary glycoproteins by c - translucent (colourless) selective adsorption(glycoproteins = mucins) in  - Can’t see it with naked eye saliva  ‐ to the enamel. - Stains positively for proteins, carbohydrates and Adsorption by specific interaction between calcium ions on lipids the tooth surface and glycoproteins in saliva, involving electrical charge. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 8 DR.ABEERABDUL SATTAR 72
  3. 3. Function & Clinical Significance Of Dental  Pellicle Protective functions d. Reforms very rapidly on the clean tooth a. Reservoir of ions eg., calcium, phosphate and fluoride ions surface within seconds b. Acts as a semi-permeable membrane. may influence the movement of ions especially of calcium and phosphate ions from the external environment into the tooth. e. Takes 1 week to mature e (impt in demineralisation- remineralisation, allows ion exchange) c. Restricts diffusion of acids - protects enamel from minor acid attackProtects the enamel surface from acid attack areas without pellicle more rapidly damaged than those with intact pellicle. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 10 DR.ABEERABDUL SATTAR 9 Damaging functions a. Influences which bacteria colonise the tooth. Specific proteins which make up the pellicle having affinity for some bacteria and not others (whatever is on d. Lubricant - can protect tooth from wear. Acts as a the surface of pellicle will determine which bacteria will lubricant, protects the tooth surface from wear during attach). THUS plays a role in dental plaque formation. mastication (chewing/grinding). b. Nutrient supply (glycoprotein) for some bacteria in dental b N ti t l ( l t i )f b t i i d t l e. Antibacterial factors – IgA, Lysozyme plaque/biofilm DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 12 DR.ABEERABDUL SATTAR 113
  4. 4. Dental plaque/Dental Biofilms The soft, non-mineralised deposit which forms on C. Presence of pellicle alters surface energy of teeth (and dental prostheses) that are not tooth (impt in use of dental adhesive materials need to adequately cleaned remove it before bonding of tooth coloured restorations) Due to scientific advances we have learnt more d. Difficult to remove with toothbrushing about the true nature of plaque: it is currently viewed as a “Biofilm” professional cleaning needed DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 14 DR.ABEERABDUL SATTAR 13 Definition of a biofilm - Biofilm is a living, well organised, co- operating community of micro-organisms and their environment. Biofilm is a living, well organised, co-operating Another definition community of micro-organisms and their Biofilm= a matrix enclosed bacterial population environment. eg; slime on rocks found in streams; slime adherent to each other and or surfaces or formed in dental waterlines; oil p p pipes, fish tanks, contact interfaces, ecological communities that evolved lenses. to permit the survival of the whole community. Bacteria in the film communicate with each Thus a dental biofilm = a diverse community other, build intricate interwined structures and (predominantly bacteria) found on the surfaces of teeth even have a primitive circulatory system. (and oral tissues and prosthetic devices) embedded in a Biofilms can be seen as positive eg used for matrix of polymers of bacterial and salivary origin detoxification of waste water but often biofilms provide a challenge for humans eg; legionnaires disease (in air-conditioning units). DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 16 DR.ABEERABDUL SATTAR 154
  5. 5. What is the clinical appearance of Thus a dental biofilm = a diverse community dental biofilm ? (predominantly bacteria) found on the surfaces of teeth (and oral tissues and prosthetic devices) Colour If thin – it is invisible embedded in a matrix of polymers of bacterial If thick – variable clinic appearance and salivary origin adults: white -yellowish children: white – can be coloured (brown, orange, (brown orange green - depends on type of bacteria – chromogenic bacteria can cause plaque to be coloured) Texture – sticky we refer to plaque as being sticky because of its ability to adhere to the tooth surface and its v hard to rinse off Thickness – variable, depends on how long plaque has been accumulating undisturbed and the amount of sucrose in the diet; – if  lots of sucrose thicker plaque DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 18 DR.ABEERABDUL SATTAR 17 Sub-gingival plaque - plaque which grows apical to the free gingival margin. - plaque is usually thin in these sites as its growth is restricted by the Location of dental biofilm gingiva. Supragingival plaque - Tongue Eg., occlusal, contact areas, cervical areas of the teeth. Why Each site - the plaque will vary in their microbial content Why ? here ? Each site in around the tooth varies therefore providing different - protected areas, hard to brush well and thus can be conducive environmental conditions for the bacteria.eg o2 levels, nutrient environment for bacteria to flourish i t f b t i t fl i h supply. Think of difference bt supra vs sub gingival plaque. plaque growing on the surfaces of teeth at or above the free gingival (Thus each area provides its own ecological niche) margin. • Restorations/ortho appliances/dentures/implants - plaque can become very thick in these areas. WHY ? Because not confined to any barriers eg. gingival tissues - dento-gingival margin is the most common site for plaque growth. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 20 DR.ABEERABDUL SATTAR 195
  6. 6. Bacteria in dental biofilm Structure of dental biofilm more than 500 different types of bacteria Bacteria - account for about 2/3 of the volume 1 cubic mm of plaque weighing 1mg has Plaque matrix - supports and surrounds the bacteria - 1/3 of the volume 100, 000,000 bacteria ! 100 000 000 b t i - 80% plaque is water & 20% solids Ranges from few bacterial cells thick or in stagnation Complex structure – (cf pellicle which is homogenous/amorphous) Heterogenous = Not uniform  because variety of factors result in accumulation  areas may reach up to 1mm in thickness. of plaque on teeth.  exhibits palisades = columns of cells at 90 degrees to the tooth surface in  micro‐colonies distributed throughout an intercellular plaque matrix DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 22 DR.ABEERABDUL SATTAR 21 Types of Bacteria found will vary depending on Bacteria found in different sites varies Age: because of : immature plaque – young plaque in age; more aerobic bacteria/less Nutrient supply pathogens Eg:Availability of nutrients from mature plaque - older plaque; more anaerobic bacteria/more pathogens Saliva Site: supragingivally vs subgingivally Gingival crevicular fluid Gi i l i l fl id Plaque found in each of these areas [Supragingivally pit/fissure vs Dietary intake of host - fermentable CHO’s/sucrose smooth surface vs interproximal & Oxygen & pH levels Supragingival Vs Subgingival ] is very different in terms of the bacteria present Thus each area provides its own ecological niche. Presence of disease: caries vs gingivitis Vs periodontal disease plaque from person to person is very different DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 24 DR.ABEERABDUL SATTAR 236
  7. 7. Types of plaque (location) To cope within a hostile environment micro-organisms must find a safe haven in relation to their neighbours and the oral environ. A favourable location = ecological niche Different plaques form in the different areas of the tooth; different environments thus favour different bacteria. Thus plaque distribution is not uniform. Also certain diseases caused/contributed  by accumulation of plaque ‐ are site  specific.  Eg caries ‐ in areas of plaque accumulation usually. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 26 DR.ABEERABDUL SATTAR 25 Chemical composition Plaque matrix of dental biofilm - Proteins consists of: Mainly - bacterial products (bacteria, dead - Lipids bacteria, bacterial products = EPS, - Carbohydrates -bacterial extrapolysaccharides (EPS) bacterial ie: glucans(dextrans)/fructans (levans) toxins, acids) & Some - host material (salivary glycoproteins, - Inorganic compounds – calcium, phosphate and fluoride containing gingival fluid/exudate Source of the plaque matrix - bacteria (EPS + dead bacteria) = Bacteria and intermicrobial substance - salivary glycoproteins ; gingival exudate = HOST - Food debris, epithelial cells, leukocytes DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 28 DR.ABEERABDUL SATTAR 277
  8. 8. The Extracellular Polysaccharides (EPS) are: What are the properties of dental biofilm ? a. Micro-organisms are arranged in microcolonies. (The bacteria in a biofilm - impt in biofilm formation are not distributed evenly – they are grouped in microcolonies) - produced by the bacteria within the biofilm and form the bulk b. Co-operating communities of various types of micro-organisms. of the plaque matrix. EPS make the plaque sticky and because c. Microcolonies are surrounded by a protective intermicrobial matrix. its sticky and hard to rinse off the plaque with water. matrix is penetrated by fluid channels that conduct the flow of nutrients, Functions wastes, enzymes, metabolites and O2) Is not a densely tightly packed mass, It has large channels to allow fluid to flow. - a source of CHO for the bacteria when dietary supplies are low -- helpful in allowing bacteria adhere and aggregate h l f l i ll i b t i dh d t - gelatinous and help keep acids formed in plaque near the tooth - they coat the bacterial cell and help protect it from bursting from osmotic effects of sucrose - EPS give white colour to the dental plaque DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 30 DR.ABEERABDUL SATTAR 29 f. Allow the survival of the community as a whole metabolic co-operativity ecological communities evolved to allow d. Within the microcolonies are differing environments. the survival of the community as a whole (protect each other) (different pH, O2 concentrations, nutrient availability, and electric potential) the communities exhibit metabolic co-operativity e. Primitive communication system (send out chemical g.Microorganisms are resistant to antibiotics, antimicrobials & signals ) host response the matrix serves as a protective barrier Quorum sensing Sessile cells in a biofilm “talk” to each other via quorum sensing to build microcolonies and to keep water DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 32 DR.ABEERABDUL SATTAR channels open. 318
  9. 9. How does dental biofilm form ? Bacterial colonisation of the mouth Stage 1. dental pellicle formation Before baby is born the mouth is sterile. Stage 2. Initial colonisation Addition of new bacteria Micro-organisms initially colonise the mouth during Stage 3. Rapid bacterial growth birth. bi th Multiplication Bacteria then colonise mouth - from atmosphere, Stage 4. Remodelling stage/maturation food, human contact, pets. Accumulation of bacterial and host product Further changes in micro-organism populations once teeth erupt (pellicle/plaque). DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 34 DR.ABEERABDUL SATTAR 33 Stage 2 of dental biofilm formation. Bacteria can adhere to acquired pellicle via 4 proposed Initial colonisation methods Highly selective process – bacteria attach to the pellicle. - hydrophobic bonding Bacteria are selectively adsorbed on to the pellicle. Highly selective process the bacteria are not just trapped, their surface characteristics - calcium bridging (links -ve charged bact cell to -ve react with the pellicle. charged tooth surface (That is the bacteria which adhere to the pellicle are selected partly - extracellularpolysaccharides via H bonding by the surface components of the bacterial cells interacting with the glycoproteins in the pellicle. Selective binding) - surface appendage on bacteria interact ionically or via H bonding This process is rapid, beginning soon after pellicle formation - (first 8 hours) DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 36 DR.ABEERABDUL SATTAR 359
  10. 10. This process is rapid  beginning soon after pellicle  formation  1‐2 days after  S.sanguis the principle early colonizers, bind to acidic cleaning the teeth proline-rich-proteins receptors on the pellicle through fibrils. Primary colonisers are largely  Gram positive cocci eg.,  streptococci mitis, angiosis  and short rods Aerobic = oxygen loving Non pathogenic (because small and round and have smaller energy barrier to overcome they easily attach to the tooth) DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 38 DR.ABEERABDUL SATTAR 37 Stage 2 of dental biofilm formation. Initial colonisation - Cocci type bacteria Actinomyces species can also function as primary colonizers. A.viscosus possesses fimbriae that contain When a single microorganism  adhesions that bind specifically to proline-rich proteins of enables to adhere to the tooth  surface (A), it can start to  the dental pellicle multiply and slowly forms a  microcolony of daughter cells (B).  These views were taken after  plaque formation on a strip glued  to a tooth surface . Series of isolated colonies which  extend laterally and  perpendicular to the surface. Columns of bacteria then build up. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 40 DR.ABEERABDUL SATTAR 3910
  11. 11. Stage 3 of dental biofilm formation. Rapid bacterial growth (Multiplication) - Plaque has doubled in mass in 2 days. Local 8 - 48 hours) accumulations occur where bacteria adhere together. - the organisms attached to the pellicle, multiply by cell division. Matrix begins to form around the bacterial colonies. - Cocci still predominate but some filamentous organisms EPS is produced by the bacteria via metabolised sucrose. eg Actinomyces are appearing. The proportion of these More bacteria adhere because of EPS. EPS is impt in ahesion and will increase. insoulbility increases – plaque resistant to removal DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 42 DR.ABEERABDUL SATTAR 41 Stage 4 of dental biofilm formation. Remodelling/Maturation - (48 hours +) - The host begins to respond to the plaque - max numbers masses - inflammation - increasing complexity --- rods, Rapid changes occur In first 4-5 days, stable fusobacteria, spirochetes - change in environment due to around 21st day d 21 d metabolic by products produced by the bacteria. Change in pH and Oxygen levels – will influence what bacteria survive and which ones don’t. Some bacteria live happily together in a symbiotic relationship. Different bacteria live together eg., corn cob = filamentous and cocci types . DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 44 DR.ABEERABDUL SATTAR 4311
  12. 12. Characteristics of Mature Dental Biofilm Mature plaque - more G-ve (don’t attach initially due to poor attachment, able to thrive in mature plaque). Attach to surface receptors of G +ve bacteria already there. there - more facultative or obligate anaerobic (O2 intolerant) bacteria during remodelling. Eg: G-ve rods - fusobacteria; G -ve cocci – veillonellae DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 46 DR.ABEERABDUL SATTAR 45 - WHY more anaerobes in mature plaque ? Co aggregation is the ability of - Increase in plaque thickness therefore decrease new bacterial colonies to adhere to diffusion of O2 to the original bacteria. Bacteria the previously attach cells. deeper In the plaque that survive are those that can Co aggregation occurs between: tolerate a low O2 environ. Different gram +ve spp. If plaque left undisturbed then the secondary colonisers can become assoc with caries & Gram-ve & gram +ve spp. gingivitis/periodontitis In late stages of plaque formation - greater proportion of pathogenic microorganisms in it occurs between different gram – mature plaque compared to young plaque ve spp. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 48 DR.ABEERABDUL SATTAR 4712
  13. 13. Factors affecting accumulation of dental biofilm Ability to colonise Saliva - influences pellicle formation wettability and surface tension of tooth surface influences pellicle formation Ability to cause stagnation --- remain undisturbed, undisturbed sheltered and thus bacteria build up. anatomy and surface morphology of teeth influences pellicle formation influences colonisation, sheltered, undisturbed environment, areas of stagnation DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 50 DR.ABEERABDUL SATTAR 49 All factors affect plaque formation and type of c. Within the plaque factors such as bacteria that reside within the biofilm. Nutrient supply Some survive whereas others don’t. Some help each Saliva other survive. Gingival crevicular fluid Dietary intake of host - fermentable CHOs Some Bacteria can adjust their needs to accommodate very different environments. environments Interaction between host and micro-organisms eg: host antibodies, I t ti b t h t d i i h t tib di neutrophil,fluid flow Competitor organisms pH and oxygen levels DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 52 DR.ABEERABDUL SATTAR 5113
  14. 14. Ability to reduce plaque levels – How can we Clinical detection of dental biofilms minimise plaque accumulation many patients unaware of plaque present on their teeth mobility of lips and tongue (mechanical displacement) - detection influences plaque formation - physical disruption - - visual - - use of plaque disclosing agents oral hygiene practices Disclosing solutions influences p q plaque formation g good vs bad OH Aims: - assists with the visualisation of the presence of plaque for patients use of fluoride and other preventive agents - used to monitor effectiveness of plaque control measures influences plaque formation - F can affect bacterial Erythrocin - plaque is stained shades of pink-red metabolism, and affect attachment of bacteria (Tablets/ solution) Iodine - plaque is stained brown-black (stains CHO in plaque) (solution) Plaklite- use of a fluorescein based solution which has affinity for plaque but invisible in normal light. When use “Plaklite” stained plaque will have a greenish-yellow glow DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 54 DR.ABEERABDUL SATTAR 53 Clinical photos of the typical topography of plaque growth. Initial growth starts along the gingival margin and from the interdental space (areas protected against shear forces), to extend farther in a coronal direction. This pattern may fundamentally change when the tooth surface contains presents irregularities (midbuccal area). DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 56 DR.ABEERABDUL SATTAR 5514
  15. 15. Removal of dental biofilm Not with water or rinsing alone Mechanically needs to be removed by - toothbrushing & flossing t thb hi fl i Important surface irregularities (left, crack on central upper incisor; right, several small pits on canine) are also responsible for the "individualized" plaque growth pattern. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 58 DR.ABEERABDUL SATTAR 57 If stop oral hygiene/tooth brushing for 9-21 days Clinical Importance of dental biofilm will see gingivitis. This can be completely The bacteria do not invade the tissues, but rather exert reversed by resuming complete oral hygiene. an indirect effect through by-products from bacterial metabolism. These by-products initiate a host response Gingivitis approx 10% of pop. can progress to (Abs, neutrophils ) against these bacterial products. - periodontitis results in Inflammation - affects bone, perio lig The bacterial species (usually anaerobic bacteria) present in plaque is more important than the amount of Risk factors = smoking, stress, poor immune plaque. Specific plaque hypothesis. Number of bacteria response, systemic disease eg. diabetes do not play a role but it’s the reaction between bacteria and the host. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 60 DR.ABEERABDUL SATTAR 5915
  16. 16. Dental Caries Dental caries Plaque is an important factor in the development of Is a result of organic acids (lactic acid) produced by dental caries. But only one of a number of factors. But it is necessary factor. cariogenic (s.mutans. lactobacilli) bacteria in plaque,dissolving the mineral (inorganic ie. plaque dissolving ie No plaque = no caries. hydroxyapatite) component of the teeth Proven by the use of germ free rats. If feed germ free rats a diet very high in sugar and other easily fermentable carbohydrate they do NOT develop dental caries. Numbers of Steptococcus mutans (& lactobaccilli) significantly associated with the plaque which leads to caries - cariogenic plaque DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 62 DR.ABEERABDUL SATTAR 61 Dental calculus Cariogenic vs non cariogenic plaque Dental calculus = latin for pebble or stone Cariogenic plaque has more S. Mutans Dental plaque in which mineralisation has involved produce IPS and EPS. both the plaque matrix and the micro-organisms. - EPS produced from metabolism of sucrose - p q becomes thicker & EPS help s.mutans plaque p With higher ie: more alkaline pH some plaque will adhere to tooth& harder for saliva to dilute the mineralise. bacterial acids Last stage in the maturation of some dental biofilms - IPS (energy store) help bacteria survive. • form lactic acid rapidly (acidogenic). The free surface usually unmineralised and has - Larger pH change. are aciduric (can survive in acidic conditions). living organisms. - can still cause disease. DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 64 DR.ABEERABDUL SATTAR 6316
  17. 17. Subgingival calculus presents as a black- brownish hard mass if the gingival margin is retracted or reflected during a surgical procedure (a). Healing of the site following removal of all hard deposits (b). DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 66 DR.ABEERABDUL SATTAR 65 Clinical features of dental calculus Why does calculus form ? Subgingival calculus Results from the fact that saliva is supersaturated ‐ 60% mineralised‐ harder with respect to content of Ca and PO4 ions. These minerals contribute to the mineralisation of plaque. ‐ dark in colour due to degradation of haemorraghic  Not all plaque mineralises (clinically see some patients exudate from gingivitis d  f   i i ii with a lot of calculus, others some and others none). ‐ thinner ‐ gets into fine root imperfections Supragingival calculus ‐ 40% mineralised‐ harder ‐ lighter in colour  DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 68 DR.ABEERABDUL SATTAR 6717
  18. 18. Materia Alba = ‘white matter’ Food Debris Consists of Food remnants adhering to the teeth , Bacteria particularily after meals. Desquamatised oral epithelial cells Food debris seen in patients with very poor OH i ti t ith seen in patients with very poor OH easily removed by water spray loosely bound - easily removed by water spray DENTAL DEPOSITS - DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 70 DR.ABEERABDUL SATTAR 69 Deposit Adherence to structure Method of tooth removal Dental plaque Close Structure is no effect by attachment definite rinsing, (removed by brushing and scaling) Materia alba Loose Amorphous dislodged by adherence structure forceful rinsing Food debris No adherence No structure dislodged by rinsing DENTAL DEPOSITS - DR.ABEERABDUL SATTAR 7118

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