Biomedische toepassingen voor het incrementeel omvormen

Starting from the extensive background knowledge built up in the domain of incremental sheet forming in the Production Engineering research group, a range of ambitious application domains come within reach that by themselves create new research challenges. An important cluster of applications is situated in the bio-medical domain. Being able to generate thin shell structures from high strength materials in a fast and flexible way and tailored to patient specific geometry, creates a number of perspectives for improved and in some cases totally new, break through medical applications. In contrast with material growth techniques, better known as ‘additive manufacturing’ or ‘3D printing’, incremental forming allows to manufacture parts with negligible thickness and weight. For orthopaedic applications, be it to treat the consequences of trauma or in a context of reconstructive or regenerative treatment after surgical removal of a tumour, the availability of strong, thin walled structures tailored to the patient forms a new opportunity. Besides a range of medical applications for which no advanced multi-disciplinary research may be required, and that will be explored using other financing channels, the following boundary shifting applications were identified:

Cranial and maxillo-facial implants:

Accurate, thin walled, high strength structures for skull reconstruction, either cranial or maxillo-facial, can eliminate negative features linked to the presently used materials. Currently brittle materials, like PMMA, or relatively soft materials, such as medical grade Ti-alloys, are being used for this purpose. The available laser supported SPIF technology allows to test the use of, for example, TiAlV as a high strength alternative. The capability to flexibly conceive and manufacture new implant designs will also allow to test combinations of materials in order to minimise unwanted effects, such as stresses caused by thermal expansion of metallic cranial implants.

Clavicula fracture treatment: The present implants for complex fractures often cause soft tissue irritation because of their relative bulkiness and the lack of interposed tissue between the skin and the implant. This results in a prolonged rehabilitation and repeated surgery in order to remove symptomatic hardware. The large skin incisions which are typically used for this surgery can cause ugly scars and can cause injury to the crossing nerves. An individualized, high strength implant is anticipated to reduce the surgical trauma and promote anatomical healing (which relates to good function).

Defect fracture treatment: Large bone defects after fracture/infection remain a tremendous challenge for the trauma surgeon. In order to obtain a relatively quick recovery it would be interesting to fill the defect with a bone chamber of which the personalised shape would be partially load bearing and the central chamber does allow seeding with bone graft and bone inductive/conductive materials in order to obtain a solid healing over time.

Starting point for all methodological developments oriented to part design and manufacture of the envisaged medical implants and surgical tools shall be digital images derived from CT scans to be processed in a virtual design environment. The use of physical sculpturing and analogue models will be avoided. The development of generic methods and techniques, that allow treatment of a wide variety of patient specific geometries, is explicitly targeted.