nCATS Seminar

Seminar 13th June 2012 4 p.m. Building 7, Room 3031

Web page: http://www.southampton.ac.uk/ncats/
Categories: Finite elements
Submitter: Luke Goater

Dear all,

The next nCATS seminar will be held on Wednesday the 13th of June in room 7/3031 at 4pm.

The presenters will be:

Richard Critchley

Fabrication of novel auxetic microstructure through the application of 3D printing and finite element technologies

Ever since their inception, auxetic foams have been the subject of considerable research but have yet to see any commercial applications owing to their high variability and low reproducibility resulting from current fabrication methods. To harness the potential of auxetic foams, a repeatable fabrication method is required.

One potential method for achieving this is through the implementation of 3D printing technologies, coupled with finite element software. Combined these two systems not only offer large working environments and high resolutions, but also allow for a feedback system to be employed such that novel microstructures can be designed, digitally tested, printed and finally mechanically tested, allowing for design optimisation (figure 1).

Kuan Yong Ching

Mechanical Adjustable and Biodegradable Implant Materials for Treatment of Articular Cartilage Defects in Knee- and Hip Joints

Articular cartilage (AC) injury is a common disorder in young people with road traffic or sports accidents present the highest risk, but it is also rising due to higher life expectancy and a more active lifestyle of the older generation. According to estimation by National Health Services UK, there are 10,000 patients suffering from cartilage damage warranting repair each year. If not treated properly, AC defects may progress into secondary osteoarthritis and total joint replacement surgery will be required. Despite great efforts, current surgical treatments for cartilage repair are still unsatisfactory. The repaired cartilage often develops into mechanically inferior fibrocartilage that cannot bear the loading and gets worn out of the defect site. Tissue engineering holds great promise for the generation of functional cartilage tissue substitutes. In our approach, we aim to support the body’s self-healing capability based on three strategies: First, we fabricate a scaffold with nanofibrous structure that mimics the fibrillar collagen meshwork of native cartilage. Second, we adjust the mechanical properties of the meshwork by varying the chemical compositions of the meshwork so that it can resist loads and adapt to stresses in the surrounding tissue. Third, the substitute material should be biodegradable to allow ingrowth of new cartilage until it is adsorbed completely by the body. So far, we have electrospun chitosan-poly(ethylene oxide) (PEO) nanofibres with diameters approximately 100 nm that is similar to the diameters of collagen fibrils in native AC. To improve their stability in physiological conditions, the loose nanofibres were crosslinked by the crosslink agent genepin. In the next stage of my research, we will produce three-dimensional scaffolds seeded with chondrocytes that can be implanted into the defect site. Likely, the mechanical properties and degradation rate of the produced scaffolds need to be adjusted by altering their chemical composition. We hope that this research can assist the body to regenerate cartilage and provides a significant contribution in restoring joint function for the patients who endure joint-related injuries.

Refreshments will be provided.