In the treatment of single-tooth gaps, the resin-bonded fixed partial denture (FPD) has established itself as an alternative treatment modality. With the advent of high-strength ceramics, such as aluminum oxide ceramics, it appeared to be possible to fabricate all-ceramic resin-bonded FPDs without a metal reinforcement. However, fractures of the traditional two-retainer design of these restorations occurred quite frequently. It was proposed to change the two-retainer design to a single-retainer design with the hope that the survival rate could be improved. Nevertheless, the use of aluminum oxide ceramics can be problematic. The present study strongly suggests that the clinical performance of resin-bonded FPDs made of a high-strength glass-ceramic is in large measure dependent on their design.