Multifunctional 3D-Printed Polylactic Acid/Hydroxyapatite Systems for cranial applications: Functionalization and Local Anti-Inflammatory Drug Delivery

Traumatic Brain Injuries (TBIs) frequently require cranioplasty procedures to restore skull integrity and protect underlying brain. Conventional cranial implants are often limited by inadequate osteointegration, risk of inflammation, infection, or the need for secondary surgical interventions. In this study, a multifunctional strategy for cranial reconstruction is proposed, combining additive manufacturing, bioactive surface func-tionalization, and local drug delivery. Porous polylactic acid (PLA) scaffolds were fab-ricated by Fused Deposition Modelling (FDM) to obtain lightweight structures with controlled porosity. The scaffolds were subsequently functionalized with hydroxyap-atite coatings, deposited through sol-gel, to provide osteointegrative properties. To locally modulate post-implant inflammatory responses, a drug delivery system based on polycaprolactone (PCL) microparticles loaded with dexamethasone was developed and entrapped within hydroxyapatite coated PLA structures. The produced systems were extensively characterized in terms of morphology, mechanical and thermal be-havior, structural properties, biological response, and drug release behavior. Results demonstrated that the 3D-printed scaffolds exhibited homogeneous hydroxyapatite coatings, showed sustained dexamethasone release from the drug delivery system, and supported good cellular viability. Overall, the proposed multifunctional scaffolds rep-resent a promising, low-cost and customizable approach for advanced cranioplasty applications, integrating structural support, osteointegration and local an-ti-inflammatory therapy within a single system.