Fracture-Load Values of All-Ceramic Cantilevered FPDs with Different Framework Designs

The purpose of this study was to evaluate the fracture-load values of cantilevered all-ceramic fixed partial dentures (FPDs). Fifty FPDs were manufactured using a zirconia frame to replace a missing molar. The FPDs were divided into five groups, each with a different framework design. After thermocycling and mechanical loading, the load to fracture was measured. The Mann-Whitney U test was used for statistical analysis. The mean fracture-load values for the test groups ranged from 346 to 548 N. Reinforcement of the shoulder on the oral side of the occlusal wall resulted in higher fracture load values, while increasing the wall thickness of the distal abutment did not improve fracture resistance. The results indicate that all-ceramic cantilever FPDs cannot yet be recommended for clinical replacement of a missing molar.