Three-Dimensional Bioprinting Can Help Bone.

The Journal of Cranio rd developing perso R technologies towa nalized therapies to reconstruct tissues. Among challenging tissues to reconstruct especially in the craniomaxillofacial area is bone tissue. Several previously developed techniques that used tissue engineering have largely failed because of many limiting factors, such as vascularity which remains the major factor. For example, bone formation was attempted to obtain from periosteal grafts wrapped around bioabsorbable biomaterials. With bulky used biomaterials, long time is needed for materials to resorb with attending risk of adverse inflammatory reactions. Later, electrospun nanofiber-based scaffolds using various polymers were developed to mimic natural extracellular matrix and were used with various cells for tissue engineering. However, developed materials do not have high strength properties to meet mechanical challenge. Although electrospinning is a versatile technique and may be regarded by some as a form of additive manufacturing techniques, it does not allow precise control over the structure of forming construct. Other additive manufacturing 3D printing techniques do, however, offer precise control over deposition of printing material, or ink. In addition, one can combine cells to achieve bioprinting of tissues. Cells and biomaterials are mixed as bioink to produce custom-made constructs. Previously, organ bioprinting was developed by using modified commercially available ink-jet printers to print cells onto Matrigel and collagen gel. Printing of organs by using different cells was envisaged at that time. The technique has developed since, and several tissues were bioprinted. Lately, bioprinted mouse ovary, for example, was implanted and was demonstrated to be fertile with successful pregnancy and delivery followed. Bioprinting applications are growing and global 3D bioprinting market is predicted to be $1.8 billion by 2027. So far, several works reported bone bioprinting using various biomaterials, mainly natural hydrogels such as alginate alone, alginate with gelatine, alginate with gelatin and extracellular matrix, alginate and Pluronic F-127, chitosan, alginate and polyvinyl alcohol, collagen, collagen and agarose, Matrigel, gelatin and silk fibroin, hyaluronic acid (HA), or carboxymethyl cellulose (CMC). In some