Sacrificial‐Template Fabrication of Orientation‐Controlled Porous Titanium Lattices With Bioactive Surfaces

ABSTRACT Porous titanium scaffolds for bone repair require coordinated control of pore architecture, mechanical behavior, and surface bioactivity. Here, we report a sacrificial‐template route based on polymer 3D printing that produces orientation‐controlled porous titanium scaffolds with hierarchical macro‐ and microporosity without direct metal additive manufacturing. Polylactic acid lattices printed by fused deposition modeling are infiltrated with a titanium powder slurry and then subjected to template removal and sintering. The process yields ortho‐grid, tri‐lattice, and quad‐lattice structures with approximately 26% isotropic linear shrinkage, 65%–67% porosity, preserved geometric fidelity, and a relative density of approximately 95% in the sintered strut walls. Uniaxial compression tests reveal architecture‐dependent behavior along the tested loading direction, whereas finite element simulations predict lower directional sensitivity under off‐axis loading as strut‐orientation diversity increases. Micro‐arc oxidation forms a Ca–P‐containing microporous oxide layer and improves cell spreading, proliferation, and alkaline phosphatase activity relative to untreated titanium scaffolds in vitro. In a rat calvarial defect model, uncoated titanium scaffolds achieve bone regeneration comparable to commercial porous tantalum, while micro‐arc oxidation further enhances bone formation. Fabrication of cone augments and other non‐prismatic geometries further demonstrates the adaptability of the approach to complex implant‐relevant structures.