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11 Cards in this Set
- Front
- Back
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Calculus definition |
mineralized dental biofilm that is filled with crystals of various calcium phosphates covered with a layer of nonmineralized dental biofilm containing viable, active bacteria the hard, tenacious mass forms on the clinical crowns of the natural teeth and dental implants, dentures, and other dental prostheses can form on anything that the biofilm touches |
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Calculus composition |
made up of inorganic, organic, & water % depends on age, hardness, and location of deposit from which it is analyzed chemical content is similar for both supra and sub calculus |
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Inorganic composition |
70-90% mainly Ca & P salts CO3 (carbonate), Na (sodium), Mg (magnesium), K (potassium) Trace elements: Cl, Zn, St, Br, Cu, Mn, W, Au, Al, Si, Fe 2/3 of the inorganic matter of calculus is crystalline; most abundant type is hydroxyapatite; other crystal types found are octacalcium phosphate, whitlockite, brushite |
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Organic composition |
15-20% nonvital microorganisms desquamated epithelial cells leukocytes mucin from the saliva cholesterol, phospholipids, fatty acids, sugars, proteins water |
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Supragingival calculus |
visible- on the clinical crown coronal to the margin of the gingiva usually softer than sub- depending on how long the patient has had it can be called supramarginal, extragingival, coronal, & salivary |
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Most frequent sites of supragingival calculus |
lingual surface of mand ant teeth facial of max 1st and 2nd molars related to major salivary ducts |
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Sub gingival calculus |
on the clinical crown apical to the gingival margin and on to the root surface not visible unless tissue is unhealthy and can be deflected with air generalized or localized on single teeth or a group of teeth harder heaviest on proximal surfaces & lighter on facials can be called submarginal & serumal |
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3 phases/steps of calculus formation |
pellicle formation --composed of mucoproteins from saliva biofilm maturation --microorganisms settle in, colonies form & grow mineralization |
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Formation time of calculus |
time it takes to mature to a mineral stage average is 12 days --10 days for rapid calculus formers --20 days for slow calculus formers time dependent on individual tendency |
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When does mineralization begin? |
as early as 24-48 hours if OH is neglected |
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Ways of detection of calculus |
visual examination -supra see directly, use of mouth mirror -sub see dark edges beneath gingival margin, air deflects margin & use of transillumination tactile examination radiographic examination dental endoscope |
