In vivo self-expanding engineering of bone.
In vivo bone formation and vascularization are interdependent process with complex regulatory mechanism. In vitro tissue engineering has meet great difficulty to copy all internal environment conditions, and the technology worked well only for relatively simple, thin tissues such as skin and cartilage that do not depend on a well-formed network of blood vessels to deliver food and oxygen. For more complex tissue of bone segments shot through with vessels, we hypothesize that an altered strategy might be effective: starting from in vitro tissue engineering for a thin sheet of primary product, then transferring to in vivo cultivation with a self-expanding procedure activated by interweaving metal springs of shape memory alloy (SMA). It is easy for thin sheet of engineering tissues to survive after implantation in vivo. Super-elasticity of SMA spring can gradually expand and re-shape the engineering product. More important, the continuous mechano-transduction effect can activate internal environment as a bioreactor for bone regeneration and vascularization. Our hypothesis integrates the existing knowledge and technologies, and could be a hopeful strategy for more convenient and safe use of bone engineering in clinics.
Zhou
Hong-Zhi
HZ
Department of Oral and Maxillofacial Surgery, School of Stomatology, Fourth Military Medical University, 145 West Changle Road, Xi'an, PR China. hz_zhou@yahoo.com
Yu
Hua
H
Xue
Yang
Y
D000818:Animals; D018786:Bone Substitutes; D048091:Guided Tissue Regeneration / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D008670:Metals; D010012:Osteogenesis / Q000502:physiology*; D019736:Prostheses and Implants; D011474:Prosthesis Design; D023822:Tissue Engineering / Q000295:instrumentation* / Q000379:methods
D018786:Bone Substitutes; D008670:Metals