dental cement
TRANSCRIPT
Dental luting cement
Bond StrengthStrengthFlow (viscosity)
WettingFilm thickness (<25 microns)
SolubilityWorking,Setting timeEsthetic
*Complication
Dental luting Cement
Zinc phosphatePolycarboxylateGlass ionomerRMGI cementResin cement
Zinc phosphate
Over 100 yrs of clinical experienceRoutine applicationPost-op sensitivitiesLow hardnessHigh solubilitypHNo bond with tooth
Polycarboxylate
Molecular bonding to tooth substance (2MPa)
Cost
Low F¯ releaseLow post-op sensitivitiesLow hardnesssolubility
Glass ionomer
Molecular bonding to tooth substanceF¯ releaseCost-Eff.Minimal dimentional changeOcca. post-op sensitivitiesSensitive to waterLimited application (ceramics)
(High caries risk)
(3-5MPa)
RMGI
Molecular bonding to tooth substance
F¯ releaseLow solubilityFewer post-op sensitivitiesApplication ? (ceramics,composite)
(>10MPa)
Resin cement
High adhesive quality (18-20MPa)
⇧ RetentionHigh hardnessLow solubilityAll metal, ceramic,composite(indirect)
Occa. Post-op sensitivities
Adhesive quality
Non-adhesive (zinc phosphate)
Micromechanical bonding (resin cement)
Molecular adhesion (polycarboxylate,GI,RMGI)
Dental Cement
Zinc phosphatePolycarboxylateGlass ionomerRMGI cementResin cement
Conventional
Adhesive
Advantage conventional cement
Easy handlingMoisture toleranceNo pre-Tx stepsRoutine for metal base
Advantage resin cement
Excellent mechanical propertiesHigh bond strength with pre-Tx stepHigh aesthetics/translucencySuitable for Ceramic, Porcelain, Composite,Metal
Resin cement
MatrixPrimerFillerCoupling agent
Resin cement
Matrix - DimethacrylatePrimer- DicrylateFiller - Quartz, silica Coupling agent- Silane dimethacrylate
Resin cement
Total etch Rely X ARC,Variolink II ,Calibra ,C&B
Self-etch Panavia F
Self-Adhesive Rely X Unicem
Adhesion
Dentin/enamel (micromachanical bond)Porcelain (hydrofluoric acid,Ammoniumfluoride acid)+ silane
Metal (sandblasting)(metal bonding adhesive)
Fiber post
Adhesion
Dentin/enamel (micromachanical bond)Porcelain (hydrofluoric acid,Ammoniumfluoride acid)+ silane
Metal (sandblasting)(metal bonding adhesive)
Fiber post
Adhesion
Dentin/enamel (micromachanical bond)Porcelain (hydrofluoric acid,Ammoniumfluoride acid)+ silane
Metal (sandblasting)(metal bonding adhesive)
Fiber post
Adhesion
Dentin/enamel (micromachanical bond)Porcelain (hydrofluoric acid,Ammoniumfluoride acid)+ silane
Metal (sandblasting)(metal bonding adhesive)
Fiber post
Why are fiber post?
1. Clinical success rate: Less root fracture than with metal posts: Dentine-like flexural strenght avoids the “wedge” effect of stiff and hard metal posts.
root fracture!
no local peak forces, no root fracture
metalfiber post
2. Esthetics: the new post is translucent and does not shine through ceramic or composite restorations
3. Easy and conservative removal with drills if endodontic re-treatment is required
further advantages: no corrosion, easy cutting of over-length, light-translucent...
Resin cement
Bond strength > Zinc phosphate 10 times
↑ RetentionReinforced ceramic - base CrownAdhesive system (micromachanical bond-tooth)
(chemical bond-porcelain,metal)
Low solubility↓ leakage
Pre-treatment procedure
Pre-treatment procedure
Pre-treatment procedure
Polymerization
Light-cured/Dual cure (2 vials - Base,Catalyst)
Self cure/auto cureDual cure
Adhesion
Dentin/enamel (micromachanical bond)Porcelain (hydrofluoric acid,Ammoniumfluoride acid)+ silane
Metal (sandblasting)(metal bonding adhesive)
Fiber post
Adhesive cement bonding to tooth ,alloy structure
Clinical Tips
AnestheticIsolate (pack cord)
Light cure 2-3 secInclude 3-5 shades,silaneRemove solvent-can inhibit setting of resin cement
Excess bonding –poor fit,low strength
Temp NE
Shade
Opaque –veneer + Tetracycline
Clear (translucent)Vita shade