Purpose: This study describes a mechanical chewing simulator that is able to reproduce mandibular movements in 3 dimensions and the forces exerted during mastication. The aim of this work was to validate the described device, which can be used to test the ability of different restorative materials to withstand stress. Materials and Methods: To validate the masticatory robot, 5 identical samples for each of 3 different restorative materials (an acrylic resin, a composite resin, and a glass ceramic) were created. Each sample underwent 5 minutes of chewing in the robot. The forces transmitted to the simulated peri-implant bone were collected. Two-way analysis of variance was used to evaluate the results. Results: There were significant differences between the materials, and internal comparisons also showed significant differences (P .0001). Conclusion: The different elastic moduli of the restorative materials significantly affected stress transmission at the simulated bone-implant interface, and the masticatory robot was able to identify this difference. The very low levels of variation confirm the precision of the machine during data collection and validate the reliability of the method, showing effective repeatability of the tests.