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DENTAL MATERIAL (Part 2) - Coggle Diagram

- - - - Can expand or contract based on manipulation
      - Microleakage, plaque buildup and caries can result from severe contraction
      - Excessive expansion strains pulp and cause sensitivity after surgery and filling to protrude
    - - Compressive strength of amalgam is 310 MPa
      - Stronger under compressive loads
      - Cannot withstand high tensile or bending strength
      - Bent dentin causes the amalgam to bend and develops tensile stress
    - - Occurs when solid material slowly deforms plastically under the influence of stresses
      - The higher the amount of creep, the greater is the degree of marginal deterioration
      - Causes unsupported amalgam protrusion, which fracture and leaves a ditch around the margin
    - - Amalgam tarnish and corrode in the oral environment
      - Results in formation of silver sulfide forming on the surface
      - Oxides and chlorides of tin are corrosion products found with conventional amalgam alloys and high-copper amalgams
      - Liberate free mercury and cause galvanism, which contaminates weakens gold restorations
- - - - Main component
      - For preparation of crowns, inlays, onlays, orthodonthic appliances and partial dentures
      - High compressive strength, a good film thickness and a high tensile strength
      - Composed of 90% ZnO,10% MgO ana d liquid that consists of 67% phosphoric acid buffered with aluminium and zinc
    - - Chemical attachment to teeth
      - Opaque, cannot be used for restoration
    - - Transparent adhesive, capable of attaching to tooth surface
      - Used as luting cements, adhesives for orthodontic, pit and fissure sealants, etc
      - CATEGORY
        
        Type I — luting crowns, bridges, and orthodontic brackets fall into this category
        
        Type IIa — reinforced restorative cements
        
        Type IIb — esthetic restorative cements
        
        Type III — base and lining cements
  - - - Brittle
      - Has limited tensile strength
      - Resin cements are stronger than zinc oxide eugenol
    - - Film thickness
      - Consistency of mixed cement
      - Shows cement ability to flow under pressure
      - Temperature greatly affects viscosity
    - - Luting agents may cause inflammatory reactions to the connective tissue if not compatible
      - Associated with low pH levels of the cements
    - - Tendency of cements to dissolve in oral fluids in a long term period
      - Depending on solubility, may case microleakage, recurrent caries and failed restoration
    - - Chemical or physical (mechanical) bonding
      - Bonding caused by attractive forces between molecules
    - - Variable in shades and opacities
      - Shade is usually matched with the restoration shade