Biomimetic coatings for orthopedic implants

Biomimetic techniques can be applied to metallic or nonmetallic orthopedic implants to produce calcium-deficient carbonated hydroxyapatite coatings. This coating is a bone-like material that mimics the properties of natural bone tissue to promote direct bonding with the bone (osseointegration). Other techniques, such as plasma spraying, are also available; however, such high-temperature techniques can damage the underlying substrate and are not useful for nonmetallic implants. Typically, the biomimetic technique includes a pretreatment process of the metallic implant using acid, alkali, or heat treatment prior to soaking in simulated body fluid under physiological conditions (37°C, pH of 7.4). Therefore the process is termed biomimetic. This type of coating can potentially reduce implant rejection and improve the overall outcomes of implant surgery.