Enhancing Calcium Phosphate Cements: A review of Bacterial Cellulose (BC) and other Biopolymer Reinforcements for Biomedical Applications.

Calcium phosphate cements (CPCs) are renowned for their biocompatibility and osteoconductivity, making them ideal for bone tissue engineering. However, their brittleness and low tensile strength limit their use in load-bearing applications. Bacterial cellulose (BC) has emerged as a promising reinforcement material due to its high tensile strength, biocompatibility, and biodegradability. The incorporation of 2 wt% BC into CPCs increased compressive strength from 5 MPa to 12 MPa, representing a 2.4-fold enhancement, while also improving toughness and promoting cellular interactions through its nanofibrillar structure. Additionally, hybrid composites combining BC with collagen, chitosan, or polycaprolactone (PCL) exhibit synergistic effects, further enhancing mechanical properties and biodegradability. These advancements highlight the potential of BC-reinforced CPCs for clinical applications in bone repair and regeneration. Despite these improvements, limited research addresses tensile and flexural properties, which are critical for load-bearing applications, as well as the effects of BC on injectability and setting time for minimally invasive procedures. Emerging innovations, such as electroactive BC-reinforced CPCs for stimulating bone healing, hold significant potential but remain underexplored. Future research should focus on optimising mechanical properties, validating clinical performance, and developing hybrid formulations to expand their use in load-bearing bone repairs.