Microtensile bond strength of cad-cam and pressed-ceramic inlays to dentin

CAD-CAM system is popular because of high esthetic and short fabrication time. But, there is limited information available about the microtensile bonding of luting cements to CAD-CAM inlays and to dentin. The aim of this study was to examine the bond strength of CAD-CAM (Cerec 3) and pressed-ceramic (IPS Empress 2) inlays to dentin surface by microtensile testing using two luting cements.

Standardized mesio-occlusal cavities were made in forty extracted molar teeth. An occlusal reduction of 2 mm was made; the bucco-lingual width of the proximal boxes was 4 mm, the occlusal width 3 mm and the depth of the pulpal and axial walls 2 mm. The proximal boxes were extended 1 mm below the cemento-enamel junction. Teeth were randomly assigned to 2 groups to evaluate the bonding of 2 ceramic systems, Cerec 3 (Group I) and IPS Empress 2 (Group II), to dentin. Each of the 2 groups were further divided into 2 luting cement groups, Panavia F (Group A) and Variolink II (Group B). After cementation, the teeth were sectioned into two 1.2x1.2 mm wide 'I' shape sections. The specimens were then subjected to microtensile testing at a crosshead speed of 1 mm/min. Two-way ANOVA and Tukey HSD tests were used to evaluate the results.

The mean microtensile bond strengths of Cerec 3 and IPS Empress 2 bonding to dentin with luting agents in MPa were Panavia F (13.98+/-3.44), Variolink II (14.19+/-3.12) and Panavia F (15.12+/-3.15), Variolink II (15.45+/-3.08) respectively. No significant differences were found among the 2 ceramic systems (P>.05) and 2 luting cements with regard to dentin bond strengths (P>.05).

There was no difference found between the dentin bond strength of the Cerec 3 and IPS Empress 2 inlays cemented with two luting cements.