A method for fabricating a collagen bio-ink includes steps as follows. A first component is provided, wherein the first component is to fill a collagen powder to a first syringe. A second component is provided, wherein the second component is to fill a neutral solution or an acid solution to a second syringe. A mixing step is performed, wherein the first syringe is connected to the second syringe with a Lure lock connector and pushing back and forth to mix the first component and the second component to form a hydrogel and become a collagen bio-ink.

Structures and methods for tissue engineering include a multicellular body including a plurality of living cells. A plurality of multicellular bodies can be arranged in a pattern and allowed to fuse to form an engineered tissue. The arrangement can include filler bodies including a biocompatible material that resists migration and ingrowth of cells from the multicellular bodies and that is resistant to adherence of cells to it. Three-dimensional constructs can be assembled by printing or otherwise stacking the multicellular bodies and filler bodies such that there is direct contact between adjoining multicellular bodies, suitably along a contact area that has a substantial length. The direct contact between the multicellular bodies promotes efficient and reliable fusion. The increased contact area between adjoining multicellular bodies also promotes efficient and reliable fusion. Methods of producing multicellular bodies having characteristics that facilitate assembly of the three-dimensional constructs are also provided.

Disclosed is a method for filling a root canal in a tooth. The method includes positioning a fiber in the root canal of the tooth, filling at least a portion of the root canal with an unset hydrogel composition, such that the unset hydrogel composition contacts at least a portion of the fiber, setting the hydrogel composition, thereby forming a set hydrogel, and removing the fiber from the set hydrogel, thereby leaving a channel in the set hydrogel. Methods and kits for repairing teeth are also described.

A preparation method of a hydrogel of a mercapto-modified macromolecular compound includes the steps of combining the mercapto-modified macromolecular compound with an acrylated macromolecular compound and/or an acrylated micromolecular crosslinker. The mercapto-modified macromolecular compound can be crosslinked with the acrylated macromolecular compound and/or the acrylated micromolecular crosslinker under physiological conditions to form the hydrogel. Due to the rapid mercapto-vinyl crosslinking reaction, the formed hydrogel system can be quickly gelled in situ after being injected into the body. The hydrogel is thus suitable for use in the fields of biomedicine, medical cosmetic plastic surgery and cosmetics.

A delivery device or patch is disclosed that includes a detachable hybrid microneedle depot (d-HMND) for cell delivery. The system includes, in one embodiment, an array of microneedles formed from an outer PLGA shell and an internal gelatin methacryloyl (GelMA)-mesenchymal stem cells (MSC) mixture (GMM). The array of microneedles project from a base substrate layer that may be flexible. The therapeutic device may be applied to a tissue site of interest and the base substrate layer is removed leaving the hybrid microneedles in the tissue at the site of application to deliver MSCs. Other stem/therapeutic cells may also be delivered with the hybrid microneedles.

Structures and methods for tissue engineering include a multicellular body including a plurality of living cells. A plurality of multicellular bodies can be arranged in a pattern and allowed to fuse to form an engineered tissue. The arrangement can include filler bodies including a biocompatible material that resists migration and ingrowth of cells from the multicellular bodies and that is resistant to adherence of cells to it. Three-dimensional constructs can be assembled by printing or otherwise stacking the multicellular bodies and filler bodies such that there is direct contact between adjoining multicellular bodies, suitably along a contact area that has a substantial length. The direct contact between the multicellular bodies promotes efficient and reliable fusion. The increased contact area between adjoining multicellular bodies also promotes efficient and reliable fusion. Methods of producing multicellular bodies having characteristics that facilitate assembly of the three-dimensional constructs are also provided.

This document describes a process of producing gel microparticles, which are consistent in size and morphology. Through the process of coacervation, large volumes of gel microparticle slurry can be produced by scaling up reactor vessel size. Particles can be repeatedly dehydrated and rehydrated in accordance to their environment, allowing for the storage of particles in a non-solvent such as ethanol. Gel slurries exhibit a Bingham plastic behavior in which the slurry behaves as a solid at shear stresses that are below a critical value. Upon reaching the critical shear stress, the slurry undergoes a rapid decrease in viscosity and behaves as a liquid. The rheological behavior of these slurries can be adjusted by changing the compaction processes such as centrifugation force to alter the yield-stress. The narrower distribution and reduced size of these particles allows for an increase in FRESH printing fidelity.

The present disclosure provides a coacervate composition containing a protein drug, gelatin A, sodium alginate and an acid and a wound-healing agent including the same. The coacervate composition according to the present disclosure can be useful as a wound-healing material delivery system for effectively delivering a protein drug, particularly epidermal growth factor, to a wound site in the wound-healing field.

A method for producing a 3D-printed tissue substitute is disclosed, utilizing a 3D printing device including a tank including a yield stress fluid in which the material is printed, the printing material delivered by the cartridge includes polyvinyl alcohol and gelatin, the method including a step following which, after printing the material in the yield stress fluid, a printed intermediate device is solidified in the yield stress fluid by lowering the temperature of the tank. The intermediate device is removed from the tank, rinsed and dried in order to obtain the tissue substitute.

The present invention relates to a method of filling different two-kinds of multiple inks into an ink extruding member for a three-dimensional print and a method of three-dimensional printing using the filled ink, and relates to a three-dimensional printing method using multiple inks comprising a step of applying pressure to the retained multiple inks and extruding it into a single extruding port of the extruding part to prepare an ink extruded product and printing the ink extruded product.