Optimized design of porous dental implant structures based on triply periodic minimal surface (TPMS).

Objectives: This study aims to optimize the design of porous dental implants using triply periodic minimal surfaces (TPMS) to address stress shielding caused by elastic modulus mismatch between titanium implants and bone tissue, while enhancing osseointegration through controlled porosity.

Methods: Two TPMS architectures (D-type and G-type) were modeled via MathMod and Rhino software, with porosity controlled by parameter t. Finite element analysis (FEA) evaluated mechanical properties under porosities of 40 %, 60 %, and 80 %, and stress distribution in a patient-specific mandibular model under 200 N masticatory load.

Results: Both D- and G-type structures met mechanical requirements at ≤60 % porosity. The D-type exhibited optimal stress transfer at 60 % porosity, whereas G-type at 80 % porosity exceeded yield strength due to thin walls. Porous designs reduced cortical-cancellous bone stress differences by 30-50 %, mitigating stress shielding. The interconnected network facilitated bone ingrowth.

Conclusions: TPMS-based porous implants with 40-60 % porosity balance mechanical strength and stress distribution, offering personalized solutions for bone quality adaptation. Future work should validate long-term stability through in vitro experiments.