Materials-Mediated In Situ Physical Cues for Bone Regeneration

Physical cues like morphology, light, electric signal, mechanic signal, magnetic signal, and heat can be used as alternative regulators for expensive but short-acting growth factors in bone tissue engineering to promote osteogenic differentiation and bone regeneration. As physical stimulation applied directly to the tissue cannot be focused on the bone defect area to regulate the cell behaviors and fate in situ, this limits the efficiency of precise bone regeneration. Biomaterials-mediated in situ physical cues, as an effective strategy combining the synergistic effect of materials themselves, are put forward and studied widely to promote osteogenic differentiation and bone repair efficiently and precisely. Different types of physical cues provide different choices to better satisfy the requirements for targeted bone defect repair. In this review, the recent research about different biomaterials-mediated physical cues accelerating osteogenesis in vitro and promoting in situ bone formation in vivo is introduced. Meanwhile, the corresponding possible mechanisms of various physical cues regulating cell responses are also discussed. This review provides useful and enlightening guidance for the utilization of intrinsically physical properties of functional materials to achieve efficient bone regeneration, leading to the design and construction of smart biomaterials for practical applications, and eventually promoting clinical translation. This review introduces the development of different biomaterials-mediated intrinsical physical cues accelerating osteogenesis in vitro and promoting in situ bone formation in vivo. Meanwhile, the corresponding possible mechanisms of various physical cues regulating cell responses are also discussed. Moreover, the potential strategies to further improve bone regeneration based on physical cues are prospected.image