Past, present and future development of microspheres for bone tissue regeneration: a review

Bone regeneration is a dynamic and complex process that encompasses active recruitment of osteogenic cells, proliferation and differentiation of such cells, formation of bone matrix and bone remodelling. In recent years, microspheres have garnered much attention due to their capability to serve as tissue engineering scaffolds and vehicles for drug delivery for trauma therapy. This review will present the use and evolution of microspheres over years of research in the field of bone regenerative medicine. Different types of microspheres such as polymeric, bioceramics and composite-based will be evaluated on how they play a role in aiding bone regeneration. Furthermore, the advantages and disadvantages of the applications of the types microspheres in bone engineering will be highlighted. This review will also include common fabrication methodologies utilised to produce such microspheres. Lastly, a brief perspective on the future direction of microspheres research for bone engineering will be discussed.