The use of osteoconductive substances as graft substitutes proved successful in the repair of fractures.
Osteobiologics refer to the class of engineered materials that are synthesized which promote healing of fractures and bone defects. Traditional methods of harvesting autogenous bone graft involves significant morbidity. Also, the quantity of bone available is limited. Allografts have shown significant success, the number of donors is less and the demand is high, also some allografts are found to cause postoperative infection, fracture or even disease transmission. This prompted the growth of osteobiologics.
Osteoconduction is an important aspect of osteobiologics. This is a process in which a synthetic substance (found to be osteoconductive) creates a conductive environment for the growth of a newly formed bone. The use of osteoconductive substances as graft substitutes proved successful in the repair of fractures. Also, these osteoconductive were an answer to the increasing demand for grafts in all areas of orthopedics. The list of osteobiologics has been rapidly expanding. The osteoconductive substances are used in association with a variety of proteins, demineralized bone as well as to produce osteogenic cells. The new set of osteobiologic products work by introducing osteogenic cells either by concentrating bone marrow or from blood platelets. Osteobiologics are being used as bone-graft substitutes in orthopedic trauma. Especially in cases where significant bone loss proves a clinical challenge, osteobiologic synthetic grafts offer substitution. The other aspects that have led to their rapid growth are availability, sterility and reduced morbidity.
The approved products being used for orthopedic applications in the United States include
1.Products based on naturally occurring substances such as demineralized human bone matrix, bovine collagen mineral composites, and processed coralline hydroxyapatite
2. synthetic materials such as calcium sulfate pellets, bioactive glass, and calcium phosphate cement
3. The bone graft substitutes that offer osteoconductive properties include coralline hydroxyapatite, collagen-based matrices, calcium phosphate, calcium sulfate, and tricalcium phosphate.
Osteobiologic product variations
During the last decade, the US Food and Drug Administration has approved several different types of osteobiologic products. Very few of the available osteobiologic products have been supported by appropriate clinical studies. There is a need for properly designed clinical studies to determine the safety, usefulness and cost-effectiveness of these products. These products vary in composition, structural strength, reabsorption rates, remodeling rates, as well as in their osteoinductive and osteoconductive potential. With lack of clinical data and product comparison information, determining the most suitable product for a particular application is a challenge.