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Lecture 4 Calculus_ Scaling and Root Planing

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									Lecture 4:

Calculus, Scaling and Root Planing




                      Dr.Leenu Maimanuku
                      Department of Oral Health
                      Fiji School of Medicine
Periodontal Microflora
   Non-Specific hypothesis         Specific hypothesis
     – Severity of                    – As plaque matures
       inflammation was                 and gingivitis
       directly related to the          develops, the
                                        bacterial composition
       quantity of plaque in            changes.
       the mouth
                                      – The bacteria in
                                        diseases and non-
                                        diseases sites differ
                                        in bacterial
                                        composition
Microorganisms Associated with
specific PD
   A few Gram –ve anaerobic bacteria
Healthy Gingiva
                     Plaque
                     JE, Pocket epithelium
                     Vessels, Inflammatory
                      cells, exudate
                     Fibroblasts, connective
                      tissue, collagen
                     Bone
Initial/Early Gingivitis

   p               Plaque
                    JE, Pocket epithelium
                    Vessels, Inflammatory
                     cells, exudate
                    Fibroblasts, connective
                     tissue, collagen
                    Bone
                    Course of disease
Established Gingivitis
   o               Plaque
                    JE, Pocket epithelium
                    Vessels, Inflammatory
                     cells, exudate
                    Fibroblasts, connective
                     tissue, collagen
                    Bone
                    Course of disease
Periodontitis
                   Plaque
                   JE, Pocket epithelium
                   Vessels, Inflammatory
                    cells, exudate
                   Fibroblasts, connective
                    tissue, collagen
                   Bone
                   Course of disease
Calculus

 Hard deposits that form by mineralization
  of dental plaque
 Does not cause gingivitis or periodontitis
 Is always covered by a layer of plaque
 Renders good OH difficult and creates
  plaque retentive areas
Calculus
              Supragingival
               calculus
                – Yellow-white
                  calcified deposits
                  located at or above
                  the gingival margin
               – Stains brown with
                 tobacco/food/drink
               – Frequently found
                 opposite duct
                 openings of major
                 salivary glands
Calculus
   Subgingival calculus
    – Dark brown-green-black deposits located
      beneath the gingival margin, adhering
      firmly to the root surface
    – Found particularly at interproximal sites
    – Dry tissues to allow color of calculus to be
      seen
    – Radiographically
    – Use stream of air to reflect gingival margin
    – During flap surgery
Calculus Composition

   inorganic content
    – 70-90% inorganic
    – Primarily Ca3(PO4)2
    – Also CaCO3 and Mg3(PO4)2
    – Primarily has crystalline structure:
      - hydroxyapatite
      - magnesium whitlockite
      - octacalcium phosphate
      - brushite
Calculus Composition

   organic content
    –   Protein-polysaccharide complexes
    –   Salivary proteins
    –   Desquamated epithelial cells
    –   Leukocytes
    –   Microorganisms
Calculus Attachment

 Attachment via pellicle (which also
  mineralizes)
 Mechanical locking into surface
  irregularities
 Close adaptation of calculus
  undersurface to the underlying
  cementum surface
Formation

 Mineralization of dental plaque
 Saliva- supragingival calculus
 GCF- subgingival calculus
 Ca2+ binds to CHO-protein complexes
  in organic matrix of plaque
 Crystalline CaPO4 salts precipitate
  within the intercellular matrix
Theories of mineralization
 Due to increased plaque levels of Ca and
  PO4 by increased pH of saliva causing
  precipitation by proteins in plaque binding Ca
  and PO4 by phosphatase from bacteria
  hydrolyzing organic PO4 in saliva
 Due to seeding of small foci of calcification
  (e.g. CHO-protein complexes that bind
  Ca2+), which       enlarge and coalesce
What is it?

 Scaling - using hand or powered
  instruments to remove plaque (and
  calculus)
 Root Planing - using hand or powered
  instruments to remove remaining plaque
  (calculus) and diseased/infected
  cementum
How?

   Hand instruments
    – The cutting edge of the instrument needs
      to meet the tooth at the correct angle
    – Curettte
      • Universal eg. Columbia 2L/2R
      • Area Specific eg. Gracey
      • Universals need to change the angle of attack
        Graceys already have the angle incorporated
        into the instrument.
Aim:


 To remove plaque( and calculus)
 To produce a smooth root surface?
 To remove diseased/ infected
  cementum?
1960’s


   Aim was to remove any plaque and
    produce a smooth hard root surface to
    inhibit further plaque accumulation
1960’s - Problems

 But while cementum of involved roots is
  rough and irregular there is NO difference
  between accumulation of plaque on rough Vs.
  smooth root surfaces
 However there are small lecunae in
  cementum that can contain calculus therefore
  root plane to remove these
 There is no evidence to suggest that involved
  (diseased cementum) is any softer than
  uninvolved.
Tissue healing

   Evidence
    – Calculus does not have to be completely
      removed for effective clinical response.
      Almost 1/2 of sites with residual calculus
      gained more than 0.5mm attachment.
1970’s
 Aim to remove cementum bound endotoxin
 1974 Aleo ct al Found an endotoxin like
  material on root surfaces which depressed
  cell growth of tissue culture fibroblasts even
  when the cementum appeared clinically
  normal
 RP done until a hard, velvety smooth and
  glass like to tough surface was achieved.
 Most teeth had visibly dished surfaces and it
  was assumed that all cementum was
  removed near the CEJ.
1980’s

 Bacterial Products found all the way to the
  CDJ to remove all bacterial products would
  need to remove all the cementum!!
 99% of LPS in cementum could be removed
  by gentle washing in water and brushing with
  slow rotating bristle brush. Suggesting that
  the bulk of LPS was on the surface of the
  cementum and not particularly well attached.
1986 Nyman et al Study on dogs

   Produced similar contralateral defects
    then
    – Flap surgery for access
    – I side received SC and removal of
      cementum with diamond burs
    – I side received prophy
   Both sides had the same clinical
    response to Treatment
 1988 Nyman et al did a similar study to
  1986 but in humans
 Same improvement in periodontal
  health ± removal of exposed cementum
 Suggested that either:
    – Endotoxins within the cementum has been
      neutralised by the inflammatory response
      or
    – Cytotoxic bacterial products are located on
      the surface of the cementum
 "Results should not be interpreted to mean
  the removal of cementum in periodontal
  therapy must necessarily be avoided. In fact
  elimination of calculus cannot be performed
  without removal of cementum.“
 Need to consider the possible advantages of
  leaving cementum eg. less sensitivity
  therefore avoid complete removal of
  supragingival calculus.
 Smart et al 1990
 Light pressure from U/S scaler is enough to
  reduce LPS to the level of uninvolved root
  surfaces in vitro
Aim for the 1990’s
 The removal of adequate plaque and
  pathogenic bacterial products from the
  root surface to allow clinical healing and
  the removal of predisposing factors.
 This is still best achieved with hand
  instruments but requires great skill and
  experience to be good at!
2000’s
   Sonic scalers
    – 3000 – 8000 Cps
    – Tip movement linear or elliptical
   Ultrasonic
    – Magnetostrictive
       • 18000 – 45000 Cps
       • Tip movement nearly linear, elliptical or circular
       • Alternating magnetic fields causes tips to vibrate
    – Piezoelectric
       • 25000 – 50000 Cps

								
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