Dental Pulp 14

  1. Resin adhesion first achieved in what year?
    1982, mechanical hybridization
  2. Difference between resin and RMGI?
    Mechanical (hydrophilic monomer layer) vs. Chemical bond
  3. Acute effects of cavity prep?
    Hydrodynamic effect of fluid flow within tubules
  4. Tubule density increases from approx _______mm2 outer dentin to _______mm2 adajcent to pulp.
    20,000-45,000
  5. Peritubular dentin and Type 1 collagen?
    Completely devoid of it, much smaller apatite crystals
  6. Carious dentin and two layers, describe?
    Demineralized, bacteria infected dentin

    Deeper, affected layer that includes a transparent zone in which tubules are occluded by mineral deposits
  7. Extent of tertiary dentin deposition appears to be:
    the trauma of cavity prep vs. restorative materials
  8. Thickness of mature dentin?
    3mm
  9. OD extend how far into tubules?
    .1mm-1mm
  10. Deeper cutting (less than __mm from the pulp) results in direct OD injury
    .3mm
  11. Acids are (able to/unable to) destroy highly croos-linked dentin Type 1 collagen,
    unable to

    evidence shows it is host derived, activated by acidic pH
  12. What are whitlockite crystals?
    magnesium-substituted tricalcium phosphate, occlude dentinal tubules in sclerotic dentin below affected dentin
  13. What acids account for 90% found in carious dentin?
    Lactic, acetic, proprionic

    pH about 4.9

    do not diffuse across dentin more than .6mm
  14. Depth of cavities and immune response?
    Innate immunity dominates in shallow caries, bacteria are too far for adaptive phagocytosis

    Transition from innate to adap occurs in irreversibly inflamed pulps separated by less than 2mm deep carious dentin
  15. Expression which proteins is assoc. with cytoskeletal reorganization of surviving ODs after injury?
    Fibronectin-binding protein and nestin, found in apical areas of ODs
  16. What proteins are invovled in the mineralixzation of the dentin matrix?
    SIBLING
  17. How many teeth prepped for full coverage go necrotic?
    4-33% will need RCT
  18. Pulpal necrosis occurs at a rate of about _% per year for single crowns?
    1
  19. Most influential variables in pulpal injury were found to be:
    • RDT
    • Prep in abscense of coolant
    • Restorationc choice in direct pulp cap
  20. Two pulpal responses most sensitive to cavity RDT?
    ODs survival and reactionary dentin secretion
  21. ODs survival precents vs RDT?
    • 100% >1mm
    • 89% .5-1mm
    • 83% .25-.5mm
    • 68% <.25mm
  22. Greatest reactionary dentin secretion vs. RDT?
    292% inc in .25-5mm

    • less growth factors diffusing more than .5mm
    • less than .25mm causes too much injury to ODs
  23. Describe heat shock proteins?
    enhance ability of cells to withstand stress and signal upreg of defense and reparative responses during cellular injury

    help cells resist injury
  24. Temp increases and effects on pulp?
    inc of pulp temp of 5.5C irreversible injury

    inc of 11C is necrosis
  25. Extent of intrapulpal heat generated determined by?
    • Use of coolants
    • Rotation speed
    • Size, type, shape of cutting instru
    • length of time in contact with dentin
    • amt of pressure of handpiece
    • cutting technique
  26. First dentin adhesion?
    1982 by Nakabayashi

    demineralize dentin, hydrophilic layer, hydrophobic layer
  27. Dentin composition?
    • 50% inorganic
    •  30% organic
    •   20% fluid
  28. Etch and rinse adhesives, steps
    • 30-40% phosp acid 15secs (5-8um demin)
    • Rinse and apply primer (hydrophilic)
    • Air to evap acetone or alcohol vehicle
    • Apply adhesive (hydrophobic) cure
    • Bulk resin

    this is 4th generation
  29. Self etching adhesives, steps?
    • Apply acidic resin primer (penetrates smear layer) 15-20 secs and then dried
    • Adhesive now cure
    • Bulk resin
  30. 5th generation adhesive systems?
    Combined primer and adhesive: single bottle adhesive systesms

    etch-apply single bottle- two steps
  31. 6th generation adhesives?
    Self-etching primer followed by adhesive

    No etch (primer)+adhesive = two steps
  32. 7th generation adhesives?
    Combines everything:

    etch+prime+adhesives all one step
  33. Glass ionomers consist of:
    alumina, silica, polyalkenoic acid

    chemical and mechanical bond

    mechanicl: milds acids cause microporosities created in dentin surface
  34. Dynamic bond of glass ionomer?
    bonds break, new ones reformed
  35. Resin shrinkage?
    2-6%
  36. Plasticization?
    process which fluids are absorbed by hydrophilic resins

    resins swell, degrade mechanical properties
  37. Application of MMPs to dentin bonding procedures, limitations why?
    1. CHX delays or arrests MMPS?

    2. MMPs only work on etch and rinse but not in self etching adhesives

    3. CHX cytotoxicity and RDT less than .2mm

    4. what about cysteine cathepsins?

    5. a zone of resin sparse demineralized dentin always remains
  38. 3 aspects effecting pulp during dentin bonding?
    1. acid etching (dentin permeability)

    2. resin cytotoxicity (esp RDT <.5mm)

    3. microleakage (shrinkage, bonds weak)
  39. Greatest concern using resins?
    microleakage
  40. Survival rates of ODs to materials:
    • CaOH 100%
    • Polycarb 81.8%
    • ZOE 78.4%
    • resin to dentin 74.2%
    • Enamel bonding resin 48.3%
    • RMGI 43.1%
  41. Placement of RMGIs within ___mm of the pulp reduced ODs numbers by more than ___%
    .5mm

    50%
  42. Most important factors in stimulation of reactionary dentin formation?
    Trauma from prep and microleakage

    VS

    material cytotoxicity
  43. With RDT less than .5mm areas occupied by reactionary dentin, material rated?
    CaOH > Resin (dentin) > Resin (enamel) > RMGI > ZOE
  44. Effectiveness of release of TGF-B1 by material rank
    EDTA > Phosph acid > citric acid > polyacrylic > nitric acid
  45. ESDP?
    EDTA soluble dentin matrix protein prep
  46. Rank of material ability to prevent microleakage:
    RMGI > bonded amalgam > ZOE > bonded resin comp > GP > CaOH > compomer > silicate > zinc phosphate
  47. Avg replacement time of resin?
    5.7yrs
Author
Aleksbaron
ID
241705
Card Set
Dental Pulp 14
Description
Quiz 14
Updated