DENTIN BOND STRENGTH AND MICROLEAKAGE COMPARISON OF THREE DIFFERENT UNIVERSAL ADHESIVES; [Üç Farklı Üniversal Adeziv Sistemin Dentine Makaslama Bağlanma Dayanımlarının ve Mikrosızıntı Değerlerinin Karşılaştırılması]

Objectives: The aim of this study is to evaluate and compare the bond strength and micro-leakage of three different universal adhesive systems applied in self-etch mode to dentin. Materials and Methods: To evaluate bond strength, the mid-coronal dentin surfaces of forty-five human molar teeth were exposed and randomly assigned into three groups according to the following adhesive application: Single Bond Universal (3M ESPE), Optibond XTR (Kerr), and Tokuyama Universal (Tokuyama Dental) (n=15). The shear bond strength test was performed after composite build-up. Then, the fractured surfaces were evaluated using a scanning electron microscope (SEM). To evaluate micro-leakage, facial class V cavities were prepared to forty-five human premolars and randomly assigned into identical three experimental groups described above (n=15). After composite resin restoration of cavities, the specimens were thermo-cycled for 500 cycles and then immersed in basic fuchsine, sectioned, and examined under a stereo-microscope. Data were evaluated using one-way ANOVA, Tukey’s, Chi-square and Mann Whitney U tests. Results: Among the adhesives, the highest bond strength was achieved in Optibond XTR, while Tokuyama Universal showed the lowest bond strength values (p<0.05). In micro-leakage results, no significant difference was reported in occlusal margins among groups. In gingival margins, Optibond XTR showed less leakage compared to Tokuyama and Single Bond Universal (p<0.05). Conclusions: The study findings indicated that two-step universal adhesive system is more successful than one-step universal adhesive systems in bonding to dentin. Considering that bonding plays a major role in the longevity of the restoration, it can be said that the use of two-step universal adhesive systems in dentin can give more successful results. © 2021, Cumhuriyet Dental Journal. All Rights Reserved.