Effect of the Thickness of Opaque Layer Coating on Strength of Metal-resin Bonding in Repairing PFM

Abstract

To observe the effect of the thickness of opaque layer coating on strength of metal-resin bonding, by comparing the metal-resin bonding strength of specimen with different opaque specimen thickness. Methods: two metal crown materials: cobalt-chromium alloy, gold alloy. Each material was produced to the same unified specimen. Then divided into three groups: no pre-opaque layer group, thin opaque layer group, thick opaque layer group. Each set had six test specimens. Using three-point flexure test method to test the initial crack pressure, the effect of different opaque layers thickness on the metal-resin bonding strength were compared. Descriptive statistics were used SPSS10.0 software package. Use SNK variance to test. RESULTS: No significant differences on bonding strength between the metal crowns. Thin opaque layer group metal - resin bonding strength was significantly greater than the thick opaque layer group’s (P <0.05); The bonding strength of the two groups’ specimens which coated opaque layer are greater than not coated opaque layer groups’, the differences was significant(P <0.05). Conclusion: Coating a thin opaque layer can increase metal-resin bonding strength, the opaque porcelain layer thickness should be controlled in order to increase the metal - resin bonding strength, in the clinical operation of PFM filling porcelain.