Comparative Evaluation of Maxillary Full-Mouth Implant Prosthesis Designs: Symmetrical Segmental Splints vs. Complete Splints in Two Occlusal Schemes

Abstract

In full-mouth implant prostheses of the maxilla, prosthetic framework design and occlusal pattern critically affect stress distribution and implant stability. Improper design may lead to localized stress accumulation, mechanical failure, or peri-implant bone resorption. This study aimed to compare the biomechanical effects of two prosthetic designs under two different occlusal schemes on stress distribution within the implant system and surrounding bone. This cross-sectional experimental study employed Finite Element Analysis (FEA). We reconstructed a 3D model of the maxilla from CBCT images and designed implants, abutments, and crowns using Mimics, 3-Matic, EXOCAD, HyperMesh, and ANSYS. We created sixteen distinct models representing different combinations of prosthetic design and occlusal pattern. A 200 N load was applied vertically and obliquely (30°) to evaluate Von Mises stress, strain, and deformation across implant components and bone structures. The canine-guided occlusal pattern generated higher stress levels in the abutment, screw, fixture, and surrounding bone compared with the group function scheme. Model M2 in the canine-guided group showed the highest stress (215.73 MPa at the abutment and 61.27 MPa at the cortical bone), while model M6 in the group function pattern showed the lowest stress values. The group function pattern demonstrated a more uniform stress distribution and reduced concentration in critical areas. Complete-splinted prostheses also showed better biomechanical performance than segmental-splinted designs. Proper selection of prosthetic design and occlusal scheme plays a vital role in enhancing implant long-term treatment success.