Abstract
Additive manufacturing (AM) has revolutionised the fabrication of architected lattice structures, enabling tunable mechanical properties, enhanced fatigue resistance, and biointegration, making them suitable for biomedical, aerospace, and high-performance structural applications. Among these, triply periodic minimal surface (TPMS) lattices and stochastic porous networks have demonstrated superior stress shielding mitigation, fatigue behaviour, and osseointegration potential compared to conventional strut-based designs. Functionally graded TPMS scaffolds improve fatigue life by up to 30% compared to uniform designs, whereas biomimetic gyroid and primitive lattices enhance bone ingrowth and vascularisation, closely mimicking native bone morphology. Despite these advantages, understanding their behaviour under multiaxial fatigue remains limited, posing challenges for practical applications. Post-processing effects and pore size optimisation for tissue integration remain critical challenges that require further investigation. This review evaluates AM lattice structures’ mechanical behaviour, fatigue performance, and osseointegration potential. Functionally graded TPMS scaffolds improve fatigue life by up to 30%, whereas biomimetic gyroid and primitive lattices enhance bone ingrowth and vascularisation, closely mimicking native bone morphology. Post-processing strategies, such as hot isostatic pressing and electropolishing, significantly affect the fatigue life, surface roughness, and mechanical properties. Research is needed to optimise pore size distribution and multidirectional porosity gradients to enhance biomechanical adaptation and long-term implant stability.