Cavity liners & cements

Cavity liners & cements

1. Requirements

   • Thermal protection
   • Chemical protection
   • Electrical protection
     • Galvanic pain (amalgam)
   • Insoluble
   • No interference with filling setting reaction
   • Radiopaque

2. Calcium hydroxide

   • Composition
     • 2 pastes - base & catalyst
   • Setting reaction = Chelation
   • Advantages
     • Alkaline
       • Anti-microbial
       • Encourages tertiary dentine deposition
     • Compatible with composite
     • Bacteriostatic
   • Disadvantages
     • Very soluble
     • Weak
   • Types
     • Setting
       • Cavity liner
         • With amalgam for deep cavities but GIC on top (stepwise)
       • Direct pulp cap
       • Indirect pulp cap
         • Stepwise excavation
       • Pulpotomy traumatised permanent teeth
     • Non-setting
       • Pulp access temporisation

3. ZOE

   • Composition
     • Zinc oxide
     • Eugenol
   • Setting reaction = Acid base
     • Setting time 24hrs
   • Advantage
     • Thermal, chemical & electrical insulator
   • Disadvantages
     • Very soluble
     • Weak & brittle
     • Not compatible with composite
   • Uses
     • Liner in Pulpotomy (CDH)
       • GIC placed on top then composite or PFMC
     • Temporary restorations/liner
       • Sedanol
         • Accelerated WT to 5 mins
         • Accelerated ZOE
       • Cavit
       • Kalzinol
         • Resin-bonded ZOE
         • Good for load bearing areas
         • Increased strength
     • Cement
       • Tempbond
     • Antimicrobial paste in reversible pulpits
       • Odontopaste
     • Grossman's sealer

4. GIC

   • Least soluble
   • Strongest
   • Compatible with composite
   • Indications
     • With amalgam for moderately deep cavities
     • Aquacem = PFMC & FMC with no retentive factors
     • Ortho
   • Aquacem

5. EBA

   • Type of ZOE
   • Used as a cement

6. Zinc Phosphate

   • Powder
     • Zinc + magnesium oxides
   • Liquid
     • Phosphoric acid
   • Increase the working time by adding the powder in small increments
   • Luting Cement

7. Zinc Polycarboxylate

   • AKA Poly F
   • Powder
     • Zinc & Magnesium oxides
   • Liquid
     • Polyacrylic acid
   • Use
     • Temporary luting cement
     • Ortho
       • Good with stainless steel
   • Opaque

8. Resin Cements

   • E.g
     • Multilink
     • Panavia
       • Uses
         • Metal onlay
         • RBB
         • Unretentive prep for all metal or PFM crown
   • Use
     • Cement EMAX, RBB, or indirect composites
     • Unretentive restoration
   • Disadvantages
     • Technique sensitive
     • Moisture control
     • Polymerisation shrinkage