[en] Poly(lactic acid) (PLA) is a biodegradable polyester that has been exploited for bone tissue engineering. The incorporation of bioactive compounds such as SiO₂, MgO, and β-tricalcium phosphate (TCP) aimed to accelerate cell proliferation, improving the material's ability to regenerate in vivo tissues. We modified a PLA-TCP composite (90 wt%-10 wt%) with 1, 5, and 10 wt% of SiO₂ and MgO, separately. Filaments were prepared in the melted state using a twin-screw extruder and used to print scaffolds by fused filament fabrication (FFF). The modification with SiO₂ leads to similar thermal and rheological behavior of neat PLA and PLA-TCP, while the incorporation of MgO induced the degradation of the polymeric matrix, causing a decrease of the crystallinity and the viscosity of the material. The scaffolds manufactured by 3D printing presented homogenous dispersion of the additives into the PLA, reproducible structure, and appropriate mechanical properties for bone replacement. (author)