  To respond to the increasing need for bone repair strategies, various types
of biomaterials have been developed. Among those, calcium phosphate ceramics
(CPCs) are promising since they possess a chemical composition similar to that
of bones. To be suitable for implants, CPCs need to fulfill a number of
biological and mechanical requirements. Fatigue resistance and toughness are
two key mechanical properties that are still challenging to obtain in CPCs.
This paper thus reviews and discusses current progress in the processing of
CPCs with bioinspired microstructures for load-bearing applications. First,
methods to obtain CPCs with bioinspired structure at individual lengthscales,
namely nano-, micro-, and macroscale are discussed. Then, approaches to attain
synergetic contribution of all lengthscales through a complex and biomimetic
hierarchical structure are reviewed. The processing methods and their design
capabilities are presented and the mechanical properties of the materials they
can produce are analysed. Their limitations and challenges are finally
discussed to suggest new directions for the fabrication of biomimetic bone
implants with satisfactory properties. The paper could help biomedical
researchers, materials scientists and engineers to join forces to create the
next generation of bone implants.
