Researchers at Texas A&M University use biological 3D printing materials to make facial bone grafts

China3D printingNet June 8th, researchers from Texas A&M University will3D printing, The combination of biomaterial engineering and stem cell biology has created a new, more efficient, and customizable bone graft material.
Using these three technologies, scientists have created3D printingThe high osteogenic scaffold can not only promote the growth of bone cells, but also can be used as a customized shaped solid bone regeneration platform. This novel biomaterial can replace the use of metals and polymers in reconstructive surgery, allowing skin grafts to be seamlessly integrated into the patient’s skull after healing.

Roland Kaunas, Associate Professor of the Department of Biomedical Engineering, said: “The materials used for craniofacial implants are either biologically inactive and as hard as titanium, or they are biologically biologically inactive. Polymers are as soft and too soft. In our research, we have developed synthetic polymers with biological activity and mechanical strength. These materials can also3D printing, So that it is possible to manufacture craniofacial implants with customized shapes that are both beautiful and practical. “



The researchers’ biomaterials can be used to make a variety of facial implants, including implants for cheek, eye socket, and jaw surgery. The picture comes from Texas A&M University.

Need for improved bone grafting technology

Every year, 200,000 people have jaw, face or head injuries. The final surgery usually requires the use of titanium plates and screws to fix the broken bones in place, and allow the surrounding bone cells to grow and form a covering around the implant. Although this method has been relatively successful in assisting bone repair, titanium is not always integrated into the bone tissue, which may cause implant failure and, in advanced cases, further surgery.

Compared with autografts, metals and thermoplastics are also more susceptible to infection, implant extrusion and exposure, tissue necrosis, and stress shielding. Bone transplantation is considered by surgeons to be a more preferable option, but this technique also has disadvantages. The direct application of bone tissue relies on the limited source of donor tissue, causing disease in the donor site, and even so, the complex geometry of the skull cannot be easily replicated.

Researchers have determined that biocompatible polymers, especially biogels, can replace polymers and metal implants.These malleable materials are preferred because once they are loaded with bone stem cells, the gel can be3D printingInto any pre-programmed shape. In addition, unlike metal plating, the human body can dissolve the hydrogel over time without causing any lasting damage.

use3D printingBiogel for bone grafting

Although the flexibility of biogel makes it3D bioprintingIdeal choice, but their flexibility will also affect the mechanical integrity and accuracy of any parts produced. In order to make the material harder, the researchers developed a nano-engineered ion covalent entanglement or “NICE”. The formula of this mixture contains only three main ingredients: a seaweed extract called kappa carrageenan, gelatin and nano silicate particles. These elements act to stimulate bone growth and mechanically strengthen the NICE hydrogel, and the strength of the mixture is found to be eight times stronger than its individual components.
Once the mixture was prepared, the researchers added adult stem cells to the process with NICE ink3D printing, And then chemically induce stem cells to transform them into bone cells. Within two weeks of this process, scientists discovered that these cells had grown in large numbers, producing high levels of bone-related proteins, minerals and other molecules. Cell secretions form a scaffold, called an extracellular matrix, which has a unique composition of biomaterials required for the growth and survival of developing bone cells. Once the scaffold is fully developed, the bone cells can be removed and the hydrogel-based implant is ready to be inserted into the skull injury site.

According to the researchers,3D printingThe strength of the scaffold facilitates the attachment and growth of healthy bone cells, while allowing developing bone cells to penetrate synthetic materials. The hydrogel also has elasticity and toughness, can be operated manually, and can be slightly compressed, and can be pressed into defects. Due to the broad biological and physical properties of NICE grafts, researchers are keen to use this method for bone regeneration in the body for spinal fusion in the near future. “Although our current focus is on repairing the skull, in the near future, we hope to expand this technology not only for cranio-maxillofacial defects, but also for bone regeneration under spinal fusion and other injuries.” Kaunas said .

The research team found that it took less than 2 weeks for the cells to enter the NICE process. The picture comes from Texas A&M University.
Bone implants in additive manufacturing
At present, experimental new biological materials have become3D printingMany academic institutions are trying to improve the technology to achieve bone implantation.Charité, Berlin