Interfacial fracture resistance of ceramic-resin composite bilayer.

Abstract

Objective: The purpose of this study was to evaluate the relationship between interfacial crack lengths and Vickers indentation loads on ceramic-resin composite specimens. Materials and methods: Five heat-pressed ceramic specimens, with dimension of 3x4x20mm, were fabricated according to the manufacturer’s instructions. For each ceramic bar, the bonding surface was acid-etched, silanized and bonded with hybrid resin composite. The surface of bonded specimen used for indentation was polished through 0.01 mm alumina paste. The diamond pyramidal indenter was used for loading on a ceramic surface closed to the interface. Loads ranging between 0.98 - 9.8 N were used for indentation. The interfacial debonding length of each indentation load was measured. Pearson Correlation analysis was performed for a statistical analysis. Results: From Pearson Correlations, there was a positive relationship between the interfacial crack size and Vickers indentation load (R2 = 0.963). The result from linear regression analysis indicated that the interfacial crack length was directly related to the indenter load. Conclusion: There was a linear relationship between interfacial crack lengths and indentation loads. The further development of a model analysis for bilayered structure should be useful for characterizing the interfacial fracture resistance of dental bilayered specimens.