Ceramics and ceramic composites for biomedical engineering applications via Direct Ink Writing: Overall scenario, advances in the improvement of mechanical and biological properties and innovations

The growing demand for personalized ceramic devices for biomedical engineering applications, with increasingly complex shapes and properties, highlights the limitations of traditional ceramic processing techniques. In recent years, increasing attention has been drawn to ceramic-based materials produced by an additive manufacturing method commonly referred to as direct ink writing (DIW) or robocasting. However, the current challenge remains the achievement of strong mechanical reliability while preserving optimal levels of biocompatibility, bioactivity and biodegradability. Hence, the present review examines the overall scenario of this field, highlighting and analyzing the primary outcomes of studies available in the literature. It also describes the most innovative approaches. Were explored pure ceramics and composites, encompassing calcium phosphates, bioactive glasses, calcium silicates, polymer-derived ceramics and functionalized materials. The review demonstrated that DIW was mostly applied for the fabrication of scaffolds intended for bone regeneration applications and that have been, more recently, capable of attaining mechanical properties in the range of cortical bone. Dense components are comprehended as well with high relative densities achieved and commendable mechanical properties in light of the densities attained. Mechanical and biological improvement strategies for the DIW method are also presented and discussed.