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DHE132 Lecture 4 Dental cements properties and manipulation Quiz#3 SLIDE1-26

  1. Dental cements are classified by?
    ADA and the ISO (Internal Standards Organization)
  2. Three Dental Category Classifications?
    • —Functions
    • Properties
    • Intended uses
  3. The ________ regulate the materials used.
    ADA and FDA
  4. The ________publishes the certified materials in the Journal of the American Dental Association and the Clinical Products in Dentistry.
    ADA Council on Dental Materials, Instruments and Equipment
  5. The Role of the Dental Assistant & Dental Hygienist depends on?
    • expanded functions of individual state practice acts
    • —Generally, the assistant prepares and mixes materials
    • Some states allow assistant to place materials in oral cavity
  6. Dental cements typically have multiple uses:
    • All are for the protection of the pulp
    • Varnish
    • Liner
    • Base
    • Chemicals
    • Caries
    • Cutting
    • Thermal conductivity: Dentin remaining over the pulp is too thin to withstand compressive, tensile, and shearing stresses
  7. True or False
    No single cement is universally acceptable and fulfills all applications.
    TRUE
  8. Dental materials mixed chairside by the dental assistant?
    Amalgams, composites, and glass isomers
  9. materials used to prepare teeth for actual restorative materials?
    -Liners, bases, cements, and bonding agents
  10. Dental materials May be classified into three types according to?
    properties and intended use
  11. Dental materials Type I:
    Luting agents, which include permanent and temporary cements (semi viscous)
  12. Dental materials Type II:
    Restorative materials, such as glass ionomers
  13. Dental materials Type III:
    Liners or bases placed within the cavity preparation
  14. The primary purpose of luting cement is to?
    —fill the interface/Bonding or cementing together/ adhesive

    —
  15. Cements mixed to primary consistency must have thin enough viscosity to be able to flow into a film thickness of ?
    0.25 µm or less
  16. Why is Viscosity of the cement is Important?
    • the prosthesis can fail
    • intimate contact with the tooth jeopardized
    • a thick layer of cement will be exposed at the margin
  17. Tooth-Restoration Interface =
    When the tooth structure and fixed prostheses are in intimate contact, a microscopic space existsImage Upload 2
  18. Cements used for permanent or temporary luting of fixed prostheses, orthodontic bands, and pins and posts must have good ____ and ____ to provide a thin film thickness
    • wetability
    • flow
  19. Type I: Temporary Luting Cement is used when?
    • the restoration needs to be removed.
    • Temporary crown; bridge
    • —Used for provisional coverage
  20. Type I: Permanent Luting Cement is used when?
    • —Long-term cementation of cast restorations: 
    •    —Inlays
    •    —Crowns
    •    Bridges
    •    Veneers
    •    —Fixed orthodontic  appliances
  21. Type 3 : Dental Cement High-Strength Base provides?
    • —thermal insulation
    • support for restorations/occlusal stress
    • Pulp Protection:
    •   Chemical irritation
    •   Temperature changes
    •   Electrical shock
    •   Mechanical injury
    • —
  22. When is a base (Type III) often recommended?
    —In preparations with an estimated 2 mm or less dentin remaining
  23. What does Buildup(high-strength base) provide?
    • mechanical support for a restorative material when an excessive amount of tooth structure is removed or missing
    • Placing a cement buildup reinforces the remaining tooth structure.
  24. Where is Calcium Hydroxide placed?
    in a thin layer on the walls and floor of the cavity prep
  25. —Calcium hydroxide:
    • is used as a liner/low-strength base in a cavity preparation(generates secondary dentin)
    • Manipulation considerations:Max mixing time: 10-15 seconds
    • Dycal
    • Alkaline pH between 9 and 11
    • Protection can be physical, thermal, chemical or both
  26. When is Calcium Hydroxide used?
    • when dentin no longer covers the pulp, also known as exposure or direct pulp cap/pulp protection
    • Bacteria
    • Irritants
  27. What does Calcium Hydroxide —stimulates?
    reparative secondary dentin formation
  28. Sedative:
    • —Soothing effect to irritated tooth structure
    • Pulpal irritation
  29. Is a sedative a cure?
    • NO
    • just a palliative material
  30. What does a palliative material do?
    alleviates a problem without dealing with the underlying cause
  31. pulpal irritation causes:
    • bacterial effects of caries, the
    • biological response to chemicals contained in restorative materials
    • cutting of tooth structure
    • thermal conductivity of metal restorations placed over or near the pulp
    • dentin remaining over the pulp is too thin to withstand compressive, tensile, and shearing stresses
  32. What Variables Affect Cements?
    • —Mixing Time:
    •    Make sure to follow the manufacture’s directions;Mixing time, Working time, —Delivery time
    • Powder to liquid ratio:
    •    This is a delicate balanceJust like the gypsum – the ratio is based around
    • —Humidity:
    •    —Warm and humid = create a loss of water from the liquid or an addition of moisture to the powder
    • Temperature:
    •    —Some cements give off an exothermic reaction
  33. —Luting consistency:
    —spatula lifts the cement 1 inch from the glass slab
  34. Cool slab will ______ working time.
    increase
  35. Putty or Base cement Consistency:
    • —‘thick putty’: glass slab mostly used
    • —Keep excess powder to pick up and manipulate putty base
  36. Over mixed consistency:
    • Too long mixing
    • —Thick and ‘cobweb’ forms
  37. The clinician must consider both _____ and _____ properties when selecting cement for each individual procedure
    • physical
    • biological
  38. —Cements are brittle materials with good _____ strength but limited ____strength.
    • compressive
    • tensile
  39. The strongest cements are?
    resin cements.
  40. The weakest cements are?
    zinc oxide eugenols (ZOEs)—
  41. Most cements combine a __ and __ dispensed in a specific ratio
    • powder
    • liquid
  42. Cements have a tendency toward dissolving in oral fluids, leading to _____.
    microleakage
  43. TRUE OR FALSE
    Most cements disintegrate in the oral environment over time
    TRUE
  44. true or false
    Resin cements are as close as possible to insoluble
    TRUE
  45. —Cement consistency measured by its ability to ?
    flow under pressure
  46. —Primary’ consistency is mixed ?
    thin but with some viscosity
  47. —‘Secondary’ consistency is mixed ?
    to a putty-like state
  48. Which is the least viscous? PRIMARY OR SECONDARY
    PRIMARY
  49. Biocompatibility OF CEMENT?
    • —Material must work within the oral cavity/living tissue & maintain integrity: still produce desired qualities within that environment
    • Cements contain acid  = pH both at placement and after complete setting
Author
dentalhygiene
ID
337990
Card Set
DHE132 Lecture 4 Dental cements properties and manipulation Quiz#3 SLIDE1-26
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DHE132 Lecture 4 Dental cements properties and manipulation Quiz#3 SLIDE 1-26
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