Concise review: personalized human bone grafts for reconstructing head and face

Abstract

Regeneration of normal shape, architecture, and function of craniofacial tissues following congenital abnormality, trauma, or surgical treatment presents special problems to tissue engineering. Because of the great variations in properties of these tissues, currently available treatment options fall short of adequate care. We propose that the engineering of personalized bone graft customized to the patient and the specific clinical condition would revolutionize the way we currently treat craniofacial defects and discuss some of the current and emerging treatment modalities.

Figures

Figure 1.

Key strategies for engineering personalized bone grafts. (a) Bioactive scaffolds with incorporation of bioactive molecules, designed to recruit the host cells, (b) cell-seeded scaffolds, with or without additional bioactive factors, designed to foster rapid bone growth inside a scaffold providing structural and mechanical competence, and (c) autologous bone grafts grown in vitro to various levels of maturity, designed to provide immediate function along with the capacity for integration with the adjacent tissues and blood supply. The similarity to native bone tissue increases from bioactive scaffolds to cell-seeded scaffolds and to preformed bone, whereas the readiness for clinical application decreases in this same order.

Figure 2.

Tissue engineering of anatomically shaped, personalized bone grafts. Two representative, distinctly different approaches are shown for human temporomandibular joint condyle (TMJ). (A): Imaging-guided fabrication of a nonbiological scaffold by rapid prototyping (adapted from Hollister [16]; reprinted by permission of Macmillan Publishers Ltd. (B-E): Tissue engineering of living bone (adapted from Grayson et al. [50]; reprinted by permission of Proc. Natl. Acad. Sci. USA). (B): Image guided fabrication of a scaffold by micromachining of decellularized bone. (C): Perfused bioreactor with an anatomically shaped chamber. (D): Analysis and optimization of the interstitial flow through the cultured bone. (E): Living TMJ graft engineered using human mesenchymal stem cells from bone marrow.