Patient-specific finite element analysis of immediate loading in the edentulous maxilla: A single-case biomechanical evaluation of three implant configurations

Abstract Aim: Finite element analysis (FEA) is widely used in implant prosthodontics to assess biomechanical behavior and support treatment planning in complex edentulous cases. This work aimed to evaluate stress distribution patterns associated with three implant configurations (all-on-four, all-on-six, and quad-zygomatic) in the edentulous maxilla using a single patient-specific finite element model under immediate loading conditions. Settings and Design: Two CBCT scans from a single edentulous patient, acquired before and after full-arch bone grafting, were segmented to generate three digital twin models including the maxilla, implants, abutments, and a full-arch prosthesis. Materials and Methods: A unilateral oblique load of 150 N at 45° was applied to the posterior region of the prosthesis using a non-deformable distribution tool to simulate immediate functional loading. Stress distribution and displacement patterns within bone and prosthetic components were evaluated. Statistical Analysis Used: A descriptive biomechanical evaluation based on stress magnitude and distribution patterns was conducted. Results: The simulations demonstrated distinct biomechanical responses among the implant configurations. The all-on-six model showed a more uniform stress distribution with lower peak stress values compared to the other configurations. In this model, the difference between tensile and compressive cortical stress peaks was reduced relative to the all-on-four and quad-zygomatic configurations. In all scenarios, stress values remained within physiological limits reported for bone tissue. Conclusion: Within the limitations of a single patient-specific model and the absence of inferential statistical analysis, this single-case biomechanical evaluation suggests that digital twin–based finite element analysis may serve as an exploratory tool for biomechanical assessment and prosthodontic treatment planning in implant-supported rehabilitation of the edentulous maxilla.