Comparison of adhesive bonding effectiveness of resin cements and flowable composites in luting glass ceramics to dentine

The aim of this study was to investigate the effect of resin cements and composite resins applied in different bonding protocols between ceramic-bonding agent-tooth interface and to evaluate the adhesion success of the materials used in the study. 108 non-caries third molar teeth extracted due to various reasons were included in our study. The teeth were embeded in acrylic blocks and the dentin grinded was exposed from the occlusal surfaces. The teeth were divided into 9 randomized groups (n = 12). 108 ceramic samples were prepared 3 mm diameter, 3 mm high from IPS e.max CAD blocks. Four different resin cements; Variolink Esthetic DC (Ivoclar vivadent), G-cem Link Force (GC), Panavia V5 (Kuraray), Maxcem Elite Chroma (Kerr) and three different flowable composites; G-aenial universal flow (GC), Herculite XRV Ultra Flow (Kerr), Vertise Flow (Kerr) and one pre-heated composite; Enamel Plus HRI (Micerium) is luted to the prepared occlusal surfaces of the teeth with different protocols (etch and rinse, self-etch and self-adhesive) according to the instructions of the manufacturers. The specimens were thermocyled in 5 ± 2°C and 55 ± 2 °C water baths for 20 sec. Shear bond strength test was performed in a Universal Testing Machine (AGS-J, SHIMADZU) and the shear bond strengths were investigated. Failure surfaces were observed by stereomicroscope and fracture types were evaluated. Data were analyzed by one-way (Anova) test (α=0.05) . According to the findings, G-aenial universal flow luted with total etch protocol 15,42 MPa, G-cem Link Force 12,69 MPa, Herculite XRV Ultra Flow (nanohibrit fluid composite) 11,51 MPa average bond strength values were found to be significantly higher than the other samples (p <0.05). The bond strength values of the other materials in the total etch group were determined as the bond strength of Enamel Plus HRI (pre-heated composite resin) 4,84 MPa and Variolink DC (resin cement) of 3,15 MPa. The samples in the self etch group were Maxcem Elite Choroma-SE (resin cement) 3.91 MPa and Panavia V5 (resin cement) 3.69 MPa. It was also observed that the samples luted with self-adhesive procedures were very low in Maxcem Elite Choroma (SA) 0.83 MPa and Vertise Flow 1.87 MPa bond strengths. As a result, it was found that G-aeniel Universal Flow flowable composite used with total etch systems showed the highest bond strength value and it was followed by the total etch adesive cement G-cem Link Force. It has been shown that flowable composites can be an alternative to resin cements when bonded with total etch procedures. In spite of total etch applications, the bond strength of self-etch and self-adhesive applications is still controversial and their bonding performance is still to be developed.