Bioactive ceramics: Challenges and perspectives

One of the most significant accomplishments of ceramic science in the 20th century was the development of bioactive ceramics that spontaneously bond to and integrate with living bone. Many of the bioactive ceramics, represented by Bioglass(R), HA, beta -TCP, glass-ceramic A-W, self-setting calcium phosphate cements and HA coatings on metallic prostheses, have achieved significant success in clinical bone repairs and replacements. In vitro assessments using simulated body fluid, together with other cellular in vitro and in vivo assessments, have put into an extensive possession of knowledge on the surface chemistry of bioactive ceramics. The surface chemistry is the fundamental to the current challenging research, e.g., bioactive surface functionalizations that endeavor to induce bonelike apatite-forming abilities on ceramics and metals with high fracture resistance, sol-gel derivations of bioactive inorganic-organic hybrids with high malleability, acellular biomimetic processes that aim at ceramic-polymer composites with natural bonelike structure and properties, and utilization of bioactive ceramics in bone tissue engineering that may be highly advantageous over prevailing attempts utilizing natural and synthetic polymers. Bioactive ceramics and related technologies are therefore believed to continue to occupy a prime position in biomedical fields in the 21st century.