Physical and chemical aspects of calcium phosphates used in spinal surgery.

In 1983, Brown and Chow discovered the first calcium phosphate cement (CPC). This discovery opened a new era in the use of calcium phosphates (CaP) as bone substitute. The first commercial CPC have now been introduced, and porous CaP with totally new properties should follow soon. In this article, the CaP traditionally used in spinal surgery are compared with these new CaP. Particular emphasis is placed on the use of CPC for bone augmentation.