Experimental Bone Transplantation

In recent years, many of the old, well established concepts of the physiology of bone have been profoundly altered in order to become adapted to the newer beliefs. No longer is each histologic division of adult bone singled out by some one group of investigators as the sole bone-forming element. The belief is growing that the processes of osteogenesis, regeneration of bone and healing of bony defects are far more complicated than was previously thought. It is being recognized that these biologic manifestations are dependent on intricate biochemical or "humoral" phenomena with which investigators are but slightly familiar. As Leriche and Policard (1928) pointed out: "The problem of osteogenesis has passed through many phases. It has been histological and surgical and at the present time it is above all chemical.... It is now the turn of the chemists and physicists. They alone can open up new horizons by giving us