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Trilateral research methods are developed by the author integrating morphology, molecular biology (physiology and biochemistry), and molecular genetics of remodeling by means of biomechanics. Through this research method the author develops artificial bone marrow chamber using bioceramics.

The author discovers through studies on evolution of hemopoiesis that the morphology of an organism can be changed by vicissitudes of inner or outer stimuli of biomechanics, i.e., environmental factors, which act to the organism, and if these vicissitudes of biomechanical stimuli are transmitted to the next generation morphological changes can be transmitted. Through this discovery the use and disuse theory of Lamarck can be explained biomechanically in molecular genetics.

Experimental evolutionary studies are carried out as follows: developing artificial bone marrow biochambers, the author has implanted them into archetype vertebrates as well as mammals, compared them each other, and analyzed them. Developments of hemopoiesis in bone marrow chambers in phylogeny are evident as the action of the gravity in terrestrialization, which is converted into heightening of blood pressure in chondrichthyes. As conclusion use and disuse theory is evidenced in second revolution of vertebrates for the gravity to trigger genetic expression in mesenchymal cells not only producing hemopoiesis conjugated with ossification of the cartilage but inducing major histocompatibility complex (MHC).

We have developed a new artificial intervertebral disc prosthesis consisting of a triaxial three-dimensional fabric (3-DF) woven by an ultra-high molecular weight polyethylene fiber and spray-coated bioactive ceramics on the disc surface. The arrangement of weave properties led to the mechanical behavior of 3-DF disc similar to the natural intervertebral disc. Using a sheep model, total intervertebral replacement using 3-DF disc either coated by hydroxyapatite or apatite-wollastonite glass ceramics was conducted with or without initial fixation. Without the use of initial fixation, interface bony union was detected, however, the segmental motion decreased at six months postoperatively. The use of temporary fixation provided a nearly physiological mobility as well as the increased fusion rate at six months. A scanning electron microscopy showed that each fiber of 3-DF disc had a direct contact to trabecula. This study first highlighted the in vivo effectiveness of artificial intervertebral disc experimentally, and clarified further problems in clinical application.