Recently, great attention has been paid to replacing or/and enhancing biological tissues by using cells
Loading a gel holder with a structure that simulates the tissue matrix and having the required three-dimensional (3D)
However, it is challenging to mimic heterogeneous tissues formed by most organs and tissues.
A head 3D printing
system for manufacturing heterogeneous cells is proposed.
So far, simple external forms have only been implemented.
We describe a computer here.
Auxiliary design and manufacturing (CAD/CAM)
The system of this application.
Our goal is to develop an algorithm for simple, intuitive design and manufacturing of heterogeneous cells
Full gel holder with free Holder
Form 3D geometry.
Automatically generate the print path of the scaffold from the 3D CAD model, and then print the scaffold by assigning four materials; i. e.
A framework, two cells.
Filled with gel and stand.
We show the printing of heterogeneous tissue models of gel brackets formed using this method, including outer ear, kidney and tooth tissue.
These results suggest that this method is particularly promising in tissue engineering and 3D printing applications, and heterogeneous organs and tissues can be regenerated with customized geometry to treat specific defects or injuries.
There are several ways to design a 3D scaffold model, including CAD-
Based on design, implicit surfaces, and space-filling curves.
Provide a good
For specific organ or tissue defects, an organized, customized 3D structure needs to be carefully designed. CAD-
Modeling-based is the preferred way to make scaffolding using 3D printing because users are simple but powerful
Interface for commercial CAD software packages.
Solid and surface design tools for CATIA V5 (
Willy West Dassault system the company
It is used here to design the external structure of heterogeneous organizations.
As shown in the figure, the final model has two main organizational parts plus a supporting part.
The final design of these parts is exported separately as an STL file, describing the 3D surface as a triangle polygon in the Descartes coordinate system.
3D printing technology to generate 3D free
Structure is formed by vertical stacking of cross-generated 2D patterns
Part of the 3D model of the design.
The slice algorithm includes the calculation of contours (i. e.
, Outer boundary)of the cross-
Part of a continuous plane.
The separation between planes is pre-determined.
OK, give the layer thickness, and then generate the profile from the intersection between the plane and the polygon that imported STL data.
Display the resulting crossover
The profile of the section, as well as the data description of the stack.
The print path of the frame is based on cross-defined
Section profile of two units-
Fill the gel part as shown below.
First, place a continuous parallel line on the profile determined by the line spacing.
For each layer, the line of the cell
Part 1 filled with gel is perpendicular to the part of the cell
Fill the second part of the gel to minimize direct contact and mixing between cells
Then, the endpoint of the print path is determined by calculating the intersection between the line and the outline.
Minimize the total length of the print-
Head track, determine the print path as shown.
Here, the lines on each layer are assigned to a separate set of print paths to define the frame.
Similarly, the print path of the bracket is calculated based on the profile belonging to that part.
Finally, the print path of the two cells-
The part filled with the gel is placed between the lines that make up the printing path of the frame.
Displays the generated print path.
The last step of the algorithm is to generate control four-
Head printing system based on user
Definition parameters of the control head (i. e.
, Speed of the head and glue pressure).
This algorithm consists of the following two steps (see ): (i)
Check which part the print path corresponds (i. e. , frame, cell-
1 and 2 or bracket), and (ii)
Translate the two endpoints of the line according to the user-
Assign specific materials to the CNC code to control the defined parameters of the 3D printing system.
MtoBS is a custom six
Head 3D printing system and has been used to manufacture a variety of hybrid structures for organizational engineering applications.
MtoBS consists of a motion control system and a distribution system that includes six dispensers, and the motion control system enables the nozzle to translate accurately throughout the 3D workspace.
The motion system consists of a linear motor, a linear encoder, and a linear guide rail that accurately controls the position of the head in the plane with an accuracy of ± 2.
4 μm with repeatability of + 1. 0u2009μm. The -
The AC servo motor with rotary encoder is used to control the axis motion of the distribution head separately with an accuracy of ± 5.
0 μm, repeatability is + 5. 0u2009μm.
Six heads of the distribution system are connected-
Axis of the motion control system.
The two print heads contain a heating block for melting the thermoplastic biological material ejected from the narrow nozzle.
The temperature and pressure at both ends can be controlled at °c and KPA.
The remaining four heads have a Peltier block for temperature control in the range of-5 ° c to 100 ° c to maintain cell viability, print suitability, and achieve heat cross-over
Connection of gel solution.
Using the piston system, the cooled gel solution can be assigned a resolution of 1 μ l.
Therefore, MtoBS allows printing 3D mixing pre-
Organizational structure consisting of a variety of micron-grade biological materials
The scale accuracy of all six heads. Four heads (
Two air pressures-
Head and two pistons-type heads)
Used to make creatures.
Simulation structure (i. e.
Ears, kidneys, teeth). First, PCL (Sigma-
Aldrich, St. Louis, Missouri, United States, 45 000