Objectives: The purpose of this study was to examine shear bond strength of various commercial repair kits used with different all-ceramic restorations. Methods: Four intraoral ceramic repair systems: Cimara (Voco), Silistor (Heraeus Kulzer), Ceramic Repair (Ivoclar Vivadent) and CoJet-System (3M Espe) were applied on four different all-ceramic systems: IPS Empress 2 (Ivoclar Vivadent), Vita In-Ceram Alumina Blank, Vita In-Ceram Alumina slickered (Vita Zahnfabrik) and Cercon (Degudent). The specimens (10x10x3mm) were divided into substructure and veneering porcelain and were prepared with the repair material (Ø5x3mm) following the guidelines for an intraoral repair. After 24 hours of storage in artificial saliva (37° C), the prepared specimens were debonded using a shear bond strength test in an universal-testing-device (Zwick) with a crosshead-speed of 0,5mm/min until fracture (n=10). Fracture modes were examined visually and in some cases microscopally and divided into adhesive, cohesive and combined fractures. Results were statistically analyzed (ANOVA, Duncan's, pResults: In all groups with substructure material specimens were debonded adhesively at the porcelain/composite interface. Only in the group IPS Empress 2 plus Ceramic Repair half of the specimens failed cohesive in the substructure ceramic. In all groups with veneering material shear test showed cohesive fractures in the ceramic. In these cases shear bond strength of the composite resin was higher than the cohesive strength of the porcelain. The results show that CoJet-System achieves generally high bond strengths, in particular in regard with oxide ceramics Vita In-Ceram Alumina (26N/mm²) and Cercon base (16N/mm²) significantly higher bond strengths were noted. Conclusion: Results indicate that silicoating and silanization represent a suitable treatment for the intraoral repair of the materials tested in this study. Schlagwörter: all-ceramic systems, ceramic repair systems, composites, bond strength