Foamed surfactant solution as a template for self-setting injectable hydroxyapatite scaffolds for bone regeneration.

The application of minimally invasive surgical techniques in the field of orthopaedic surgery has created a growing need for new injectable synthetic materials that can be used for bone grafting. In this work a novel fully synthetic injectable calcium phosphate foam was developed by mixing alpha-tricalcium phosphate (alpha-TCP) powder with a foamed polysorbate 80 solution. Polysorbate 80 is a non-ionic surfactant approved for parenteral applications.

Factors affecting the structure and properties of an injectable self-setting calcium phosphate foam.

One of the main challenges in the investigation on calcium phosphate cements (CPC) lies in the introduction of macroporosity, without loosing the self-setting ability and injectability, characteristic of the cement-type materials. The benefits of macroporosity are related to the enhancement of bone regeneration mechanisms, such as angiogenesis and tissue ingrowth. In this work, the feasibility to obtain self-setting injectable macroporous hydroxyapatite foams by the incorporation of a protein-based foaming agent to a CPC is demonstrated.