Purpose: The objective of this study was to assess the stress distribution generated by a simulated loading (100 N) in the area of the cantilever in three different five-implant mandibular protocol prosthesis models. Materials and Methods: The finite element analysis was carried out in three-dimensional models simulating: (1) a temporary allacrylic resin mandibular protocol prosthesis; (2) a metal-acrylic mandibular protocol prosthesis; and (3) a metal-ceramic mandibular protocol prosthesis. Results: The allacrylic model promoted the highest stress values on the implant closest to the cantilever loading point. Conclusion: This study supports the need for a metallic bar reinforcement in the denture base.