The purpose of this study was to evaluate the influence of three dentin bonding agents on the shear bond strength, microleakage, and film thickness of resin cement for porcelain laminate veneer.
Dentin & enamel surfaces were treated with three dentin bonding agents sucvh as Scotchbond 2, All Bone 2, and Prisam Universal Bond 2 and were cemented by G-Cera cement for porcelain laminate veneer.
For bond strength test, the specimens were stored in 37℃, 100% humidity for 48 hours and shear bond strength was measured with Instron testing machine (model no. 4201) at crosshead speed of 1.0mm/min.
For microleakage and film thickness meaurement, the specimens were stored in 37℃, 100% humidity for 7 days, thermocycled for 1000 cycles. Microleakage and film thickness of resin cement were measured with inverted metallurgical microscope(PME
311,
Olympus, Japan).
The results were as follows :
1. The shear bond strength of resin cement for porcelain laminate veneer to dentin was enhanced by the use of dentin bonding agent and All Bond 2 were effective in improving the shear bond strength to both enamel and dentin.
2. All Bond 2 were effective in reducing microleakage of veneers bonded to dentin, approximately to the same degree to the veneers bonded to dentin, approximately to the same degree to the veneers bonded to enamel.
But Prisma Universal Bond 2 and Scotchbond 2 failed to limit microleakage at the gingival margin of veneers bonded to dentin
3. the 40% phosphoric acid in G-Cera system and the 10% phosphoric acid in All Bond 2 appeared equally effective in reducing microleakage of veneers bonded to enamel.
4. There no significant increase in cement film thickness when using Prisma Universal Bond 2 or Scotchbond 2, but with All Bond 2 slight increase in the cement film thickness were present.
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