Scientists at Texas A&M University have employed additive manufacturing, biomaterial engineering, and stem cell biology to develop materials for use in bone grafting. These materials will be easily adaptable and are cost-effective.
Using these three innovations, they were able to create using 3D printing grafting material that has a high potential to replicate the formation of bone cells. The printed scaffolds equally provide for a strong framework for the growth of bones in customized environments.
The newest material offers an additional option to metal and polymers materials that have been previously utilised for reconstructive surgery. Equally the skin graft smoothly combines into the patient’s skull on recovering.
According to Roland Kaunas, an associate professor at the Bioengineering Department, the materials that are used in craniofacial bone implants are either too hard and biologically inactive as in the case of titanium or too soft and biologically active like happens in biopolymers.
The new development however produces a replica polymer that is both bioactive and mechanically sturdy. Since this material can equally be printed using additive manufacturing, they allow for customised craniofacial implants that are creative and practical.
Medical statistics reveal that yearly, 200,000 people get injuries to their jaw bone, face or head. Repair for these injuries often entails the use of titanium plates and screws to join together the broken parts and allow for regeneration of bone cells around that area to cover the implant. Though the process is usually successful when it comes to repairing bones, titanium does not break down and get infused into the bone tissues, a factor that can cause the implant to malfunction and in extreme cases result in having subsequent operations.
Also metals and thermoplastics are prone to contamination, implant extrusion and exposure, tissue death and can cause bone density reduction in comparison to cells harvested from the same individual. While bone transplants are a favorite option for surgeons, their use comes with some setbacks. There is a limit on donor tissues when using direct application of bone tissues and there can be complications in healing of donor sites. Also it’s not possible to duplicate complex geometrical features of skull bones.
This led the researchers to develop biocompatible polymers and particularly biogels as alternatives to polymers and metal implants. The materials are both pliable and favourable since when loaded with bone stem cells, the resulting gels can then be produced using 3D into the desired shape. Additionally, the body is able to dissolve them into hydrogels without any adverse effects.
Creating bone transplants with Additive Manufactured biogels
The malleability of biogels gives them an edge when it comes to 3D bioprinting. However, suppleness in turn affects their mechanical integrity and precision of parts produced. To counter this setback, the scientists came up with a Nanoengineered Ionic-Covalent Entanglement (NICE).
It is comprised of three major ingredients, Kappa carrageenan which is an extract from seaweed, gelatin and nanosilicate particle. When combined, these three ingredients work to restore bone growth as well as mechanically strengthen NICE hydrogel producing a mixture that is 8 times stronger.