To present a sample preparation and test methodology for evaluating the fracture resistance of ceramic materials configured in a way similar to the screw-access holes found in implant-supported ceramic full-arch devices. A finite-width rectangular plate with a central hole was designed to evaluate the critical stresses of ceramic full-arch screw-access holes. Different load scenarios were investigated by comparing forces applied to BruxZir Esthetic (Glidewell Laboratories) and BruxZir Esthetic enhanced with BruxZir Steel (Glidewell Laboratories) specimens. Using the proposed test method, it was found that the fracture resistance of full-arch prostheses is largely dependent on the location of the screw-access hole and the inherent mechanical properties of the material (P < .001). The finite-width plate model may be suitable for evaluating the fracture resistance of ceramic full-arch prostheses. The fracture resistance of 3D ceramic full-arch prostheses can be greatly improved by improving the mechanical properties of the material and/or increasing the wall thickness of the screw access hole by relocation.