Demineralized Dentin Matrix (DDM) As a Carrier for Recombinant Human Bone Morphogenetic Proteins (rhBMP-2)

A bone graft and bone graft substitute should have at least one of the following properties: it should be (1) osteogenic, (2) osteoinductive and/or (3) osteoconductive. In addition, bone graft substitutes should be biocompatible and bioresorbable as well as easy to use and cost effective. Autologous cancellous bone is the clinical gold standard in bone grafting procedures1, 4 and it has osteogenic, osteoinductive, and osteoconductive properties. Because of disadvantages associated with harvesting autologous bone graft material, such as requiring an additional operation and possible donor site morbidity, there is a need for an alternative in terms of enhancing the bone healing for the treatment of large bony defects. One possible option is a newly developed biomaterial, the demineralized dentin matrix (DDM). It is based on autogenous tooth dentin and is produced through demineralization. It is osteoconductive and osteoinductive due to the fact that dentin contains extracellular Type I collagen and various growth factors. Based on the demineralization process the factors stay available to the host environment. In 1965, Urist already showed the formation of ectopic bone after implanting DDM into muscle pouches in rodents. DDM is used for example in dental surgery in the treatment of extraction socket preservation and guided bone regenerations. It functions as a scaffold to support bone regeneration, but can also be used as a carrier for rhBMP-2. When DDM serves as a carrier, it combines the properties of the grafting material with those of the delivered substances. This chapter will present the experimental and clinical studies of DDM for rhBMP-2 carrier as well as alternatives of bone graft substitute.