Calcium sulfate: a review

Calcium sulfate has a long history of use in medicine and dentistry. It exists in two forms (alpha and beta), which differ greatly in physical properties. It has been used in bone regeneration as a graft material and graft binder/extender and as a barrier in guided tissue regeneration. It is an unusually biocompatible material and is completely resorbed following implantation. It does not evoke a significant host response and creates a calcium-rich milieu in the area of implantation. These calcium ions may provide some stimulation to osteoblasts, which may account for some of the positive results reported with the material. Calcium sulfate can be used as a delivery vehicle for growth factors and antibiotics, although this application has not been thoroughly exploited in the clinical setting. It has been shown that tissue will often migrate over calcium sulfate if primary closure cannot be obtained, which provides further evidence of its biocompatibility. The raw material from which calcium sulfate is made is relatively inexpensive and abundant. Despite these advantages, calcium sulfate has never attracted the same degree of research interest as have other biomaterials. Recently, however, it has enjoyed a resurgence of sorts in the areas of periodontology, sinus augmentation, and orthopedic surgery. Future research must be directed toward improving handling characteristics and strength, while preserving the biocompatibility of the material.