On the fabrication of bioactive glass implants for bone regeneration by laser assisted rapid prototyping based on laser cladding

Abstract

The processing of bioceramic materials is a topic of great interest for bone regeneration; bioceramic implants are specifically appropriate for low-load applications, such as cranioplasty. In the present study, we investigated the capabilities of rapid prototyping based on laser cladding to generate three-dimensional bioactive glass implants without moulds or preplaced powder bed. 45S5 bioactive glass and lower crystallization tendency S520 bioactive glass particles were successfully injected and melted to obtain glass-derived implants with similar mechanical properties to the precursor materials. The role of processing parameters in the process outcome was analysed: optimization of the assist gas volumetric flow, the precursor glass mass flow, the substrate preheating, and the optical power of the CO2 infrared laser beam, allowed to adjust the material cooling rates to preclude extensive crystallization or cracking. The assessment of calcium hydroxyapatite precipitation ability and ion release in simulated body fluid conclude the potential osteoconductivity of the produced implants.