Manufacturable design and experimental investigation of functionally graded TPMS-based root analogue implant for dental applications

In recent years, triply periodic minimal surfaces (TPMS) have gained significant attention among researchers. Due to their tunable mechanical properties, these structures have the potential to effectively mimic native bone tissue and can also be used to design novel prosthetics with specific features personalized for each patient. To overcome the common disadvantages associated with traditional dental implants, we have designed and 3D printed three types of root analogue implants (RAI): 1. Solid RAI dental implant, 2. RAI dental implant with Gyroid structure and 3. RAI dental implant with functionally graded Gyroid structure. The creativity of this study lies in the design and implementation of a functionally graded gyroid-based TPMS structure in a root-analog dental implant, allowing controlled variation of mechanical properties across the implant. Topology optimization was performed on all implant models to improve stress distribution and strain energy density. Additionally, we analyzed stress distribution in TPMS-based implants with complex external geometries, in contrast to prior studies that primarily examined symmetric lattice structures. A comparative mechanical evaluation of solid, uniform TPMS, and graded TPMS RAI implants, supported by experimental validation, was carried out. We also investigated material scaling as a reliable method to reduce experimental costs. The results demonstrated an overall increase in strain energy density across all implants, with the graded implant exhibiting a 22% increase, indicating its superior biomechanical performance.